Tuesday, August 9, 2022

Number of the day: 8346

Properties of the number 8346:

8346 = 2 × 3 × 13 × 107 is the 7300th composite number and is squarefree.
8346 has 4 distinct prime factors, 16 divisors, 7 antidivisors and 2544 totatives.
8346 has a semiprime digit sum 21 in base 10.
8346 has a Fibonacci digit sum 21 in base 10.
8346 has a triangular digit sum 21 in base 10.
8346 is the difference of 2 positive pentagonal numbers in 3 ways.
8346 = 42 + 492 + 772 is the sum of 3 positive squares.
83462 = 32102 + 77042 is the sum of 2 positive squares in 1 way.
83462 is the sum of 3 positive squares.
8346 is a proper divisor of 8572 - 1.
8346 is palindromic in (at least) the following bases: 43, and 56.
8346 in base 7 = 33222 and consists of only the digits '2' and '3'.
8346 in base 34 = 77g and consists of only the digits '7' and 'g'.
8346 in base 42 = 4UU and consists of only the digits '4' and 'U'.
8346 in base 43 = 4M4 and consists of only the digits '4' and 'M'.
8346 in base 55 = 2ff and consists of only the digits '2' and 'f'.
8346 in base 56 = 2b2 and consists of only the digits '2' and 'b'.

The number 8346 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A022268: a(n) = n*(11*n - 1)/2.
A041746: Numerators of continued fraction convergents to sqrt(393).
A129025: See Mathematica code.
A213271: Costas arrays such that the corresponding permutation is a derangement.
A216423: Numbers k such that 4^k + k^4 + 1 is prime.
A217390: Numbers n such that sum of squares of digits of n equals the sum of prime divisors of n.
A252407: T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 2 3 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 2 3 4 6 or 7
A269967: Indices of zeros in A269783.
A330791: Values of k such that A005132(k) (the k-th number in the Recamn sequence) divides k.
A341477: Coefficients related to the asymptotics of generalized Delannoy numbers.

Monday, August 8, 2022

Number of the day: 4252

Properties of the number 4252:

4252 is the 1081th totient number.
4252 = 22 × 1063 is the 3669th composite number and is not squarefree.
4252 has 2 distinct prime factors, 6 divisors, 25 antidivisors and 2124 totatives.
4252 has an emirp digit sum 13 in base 10.
4252 has a Fibonacci digit sum 13 in base 10.
4252 = 10642 - 10622 is the difference of 2 nonnegative squares in 1 way.
4252 is the sum of 2 positive triangular numbers.
4252 is the difference of 2 positive pentagonal numbers in 1 way.
4252 is not the sum of 3 positive squares.
42522 is the sum of 3 positive squares.
4252 is a proper divisor of 7196 - 1.
4252 is palindromic in (at least) the following bases: -13, -21, -31, -36, and -50.
4252 in base 3 = 12211111 and consists of only the digits '1' and '2'.
4252 in base 20 = acc and consists of only the digits 'a' and 'c'.
4252 in base 32 = 44s and consists of only the digits '4' and 's'.
4252 in base 37 = 33Y and consists of only the digits '3' and 'Y'.

The number 4252 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A055328: Number of rooted identity trees with n nodes and 3 leaves.
A077297: Partition the concatenation 1234567...of natural numbers into successive strings which are multiples of 4, all different and > 4. ( 0's never taken as the most significant digit.)
A090748: Numbers n such that 2^(n+1) - 1 is prime.
A134212: Positions of 12 after decimal point in decimal expansion of Pi.
A193492: Put the natural numbers together without spaces and read them four at a time advancing one space each time.
A212585: Walks of length n on the x-axis using steps {1,-1} and visiting no point more than twice.
A239262: Number of partitions of n having (sum of odd parts) > (sum of even parts).
A272790: Number of active (ON,black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 537", based on the 5-celled von Neumann neighborhood.
A320234: Expansion of Product_{k=1..8} theta_3(q^k), where theta_3() is the Jacobi theta function.
A353255: Expansion of Sum_{k>=0} x^k * Product_{j=0..k-1} (2 * j + x).

Sunday, August 7, 2022

Number of the day: 7113

Properties of the number 7113:

7113 = 3 × 2371 is semiprime and squarefree.
7113 has 2 distinct prime factors, 4 divisors, 9 antidivisors and 4740 totatives.
7113 has an oblong digit sum 12 in base 10.
7113 has a semiprime digit product 21 in base 10.
7113 has a Fibonacci digit product 21 in base 10.
7113 has a triangular digit product 21 in base 10.
Reversing the decimal digits of 7113 results in an emirpimes.
7113 = 35572 - 35562 = 11872 - 11842 is the difference of 2 nonnegative squares in 2 ways.
7113 is the sum of 2 positive triangular numbers.
7113 is the difference of 2 positive pentagonal numbers in 1 way.
7113 = 102 + 172 + 822 is the sum of 3 positive squares.
71132 is the sum of 3 positive squares.
7113 is a proper divisor of 19076 - 1.
7113 = '7' + '113' is the concatenation of 2 prime numbers.
7113 is an emirpimes in (at least) the following bases: 4, 5, 8, 9, 10, 19, 28, 36, 44, 47, 48, 51, 60, 64, 65, 69, 70, 71, 72, 73, 75, 76, 84, 89, 94, and 100.
7113 is palindromic in (at least) the following bases: 29, 45, and -34.
7113 in base 29 = 8d8 and consists of only the digits '8' and 'd'.
7113 in base 44 = 3TT and consists of only the digits '3' and 'T'.
7113 in base 45 = 3N3 and consists of only the digits '3' and 'N'.
7113 in base 59 = 22X and consists of only the digits '2' and 'X'.

The number 7113 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A006124: a(n) = 3 + n/2 + 7*n^2/2.
A022503: Describe the previous term! (method B - initial term is 7).
A027026: a(n) = T(n,n+4), T given by A027023.
A027032: a(n) = T(n,2n-8), T given by A027023.
A033679: a(1) = 2; a(n) is smallest number >= a(n-1) such that the juxtaposition a(1)a(2)...a(n) is a prime.
A152136: a(0) = 0; thereafter a(n) is always the smallest integer > a(n-1) not leading to a contradiction, such that the concatenation of any two consecutive digits in the sequence is a prime.
A152607: a(1) = 1; thereafter a(n) is always the smallest integer > a(n-1) not leading to a contradiction, such that the concatenation of any two consecutive digits in the sequence is a prime.
A239986: T(n,k)=Number of nXk 0..3 arrays with no element equal to zero plus the sum of elements to its left or two plus the sum of the elements above it or one plus the sum of the elements diagonally to its northwest, modulo 4
A249334: Numbers n for which the digital sum contains the same distinct digits as the digital product.
A249335: Numbers n for which the digital sum contains the same distinct digits as the digital product but the digital sum is not equal to the digital product.

Saturday, August 6, 2022

Number of the day: 11168

Johann Bernoulli was born on this day 355 years ago.

Properties of the number 11168:

11168 = 25 × 349 is the 9815th composite number and is not squarefree.
11168 has 2 distinct prime factors, 12 divisors, 9 antidivisors and 5568 totatives.
11168 has an emirp digit sum 17 in base 10.
Reversing the decimal digits of 11168 results in a prime.
11168 = 23 + 83 + 223 is the sum of 3 positive cubes in 1 way.
11168 = 27932 - 27912 = 13982 - 13942 = 7022 - 6942 = 3572 - 3412 is the difference of 2 nonnegative squares in 4 ways.
11168 = 522 + 922 is the sum of 2 positive squares in 1 way.
11168 = 122 + 322 + 1002 is the sum of 3 positive squares.
111682 = 57602 + 95682 is the sum of 2 positive squares in 1 way.
111682 is the sum of 3 positive squares.
11168 is a proper divisor of 9114 - 1.
11168 is palindromic in (at least) the following bases: 36, 55, and -25.
11168 in base 13 = 5111 and consists of only the digits '1' and '5'.
11168 in base 22 = 111e and consists of only the digits '1' and 'e'.
11168 in base 30 = cc8 and consists of only the digits '8' and 'c'.
11168 in base 36 = 8m8 and consists of only the digits '8' and 'm'.
11168 in base 54 = 3ii and consists of only the digits '3' and 'i'.
11168 in base 55 = 3c3 and consists of only the digits '3' and 'c'.

The number 11168 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A046994: Number of Greek-key tours on a 3 X n board; i.e., self-avoiding walks on a 3 X n grid starting in the top left corner.
A084422: Number of subsets of integers 1 through n (including the empty set) containing no pair of integers that share a common factor.
A110735: Let n = a_1a_2...a_k, where the a_i are digits. a(n) = least multiple of n of the type b_1a_1b_2a_2...a_kb_{k+1}, obtained by inserting single digits b_i in the gaps and both ends; 0 if no such number exists.
A138744: Let r_1 = 1. Let r_{m+1} = r_1 + 1/(r_2 + 1/(r_3 +...(r_{m-1} + 1/r_m)...)), a continued fraction of rational terms. Then a(n) is the sum of the (positive integer) terms in the simple continued fraction of r_n.
A164191: Number of binary strings of length n with equal numbers of 00000 and 11111 substrings
A177482: Suppose e<f, e<h, g<f and g<h. To avoid fegh means not to have four consecutive letters such that the second and the third letters are less than the first and the fourth letters.
A185098: a(n) = floor((265/6)*4^(n-4) - n^2 - ((15+(-1)^(n-1))/6)* 2^(n-3)).
A223432: T(n,k)=5X5X5 triangular graph without horizontal edges coloring a rectangular array: number of nXk 0..14 arrays where 0..14 label nodes of a graph with edges 0,1 0,2 1,3 1,4 2,4 2,5 3,6 3,7 4,7 4,8 5,8 5,9 6,10 6,11 7,11 7,12 8,12 8,13 9,13 9,14 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph
A248575: Rounded sums of the non-integer cube roots of n, as partitioned by the integer roots: round[sum(j from n^3+1 to (n+1)^3-1, j^(1/3))].
A285152: T(n,k) = Number of n X k 0..1 arrays with the number of 1s horizontally or antidiagonally adjacent to some 0 one less than the number of 0's adjacent to some 1.

Friday, August 5, 2022

Number of the day: 2613

Niels Henrik Abel was born on this day 220 years ago.

Properties of the number 2613:

2613 = 3 × 13 × 67 is a sphenic number and squarefree.
2613 has 3 distinct prime factors, 8 divisors, 17 antidivisors and 1584 totatives.
2613 has an oblong digit sum 12 in base 10.
2613 has a triangular digit product 36 in base 10.
2613 = 13072 - 13062 = 4372 - 4342 = 1072 - 942 = 532 - 142 is the difference of 2 nonnegative squares in 4 ways.
2613 is the sum of 2 positive triangular numbers.
2613 is the difference of 2 positive pentagonal numbers in 2 ways.
2613 = 72 + 82 + 502 is the sum of 3 positive squares.
26132 = 10052 + 24122 is the sum of 2 positive squares in 1 way.
26132 is the sum of 3 positive squares.
2613 is a proper divisor of 9372 - 1.
2613 = '2' + '613' is the concatenation of 2 prime numbers.
2613 is palindromic in (at least) the following bases: 29, 66, and -30.
2613 in base 25 = 44d and consists of only the digits '4' and 'd'.
2613 in base 28 = 399 and consists of only the digits '3' and '9'.
2613 in base 29 = 333 and consists of only the digit '3'.

The number 2613 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A022288: a(n) = n*(31*n-1)/2.
A121033: Multiples of 13 containing a 13 in their decimal representation.
A130689: Number of partitions of n such that every part divides the largest part; a(0) = 1.
A140674: a(n) = n*(3*n + 17)/2.
A153875: 3 times 13-gonal (or tridecagonal) numbers: 3*n*(11*n - 9)/2.
A209032: T(n,k) is the number of n-bead necklaces labeled with numbers -k..k allowing reversal, with sum zero and first differences in -k..k.
A231855: T(n,k)=Number of nXk 0..2 arrays with no element having a strict majority of its horizontal and antidiagonal neighbors equal to itself plus one mod 3, with upper left element zero (rock paper and scissors drawn positions)
A244788: T(n,k)=Number of length n 0..k arrays with each partial sum starting from the beginning no more than one standard deviation from its mean.
A349053: Number of non-weakly alternating integer compositions of n.
A350844: Number of strict integer partitions of n with no difference -2.

Thursday, August 4, 2022

Number of the day: 48808

William Rowan Hamilton was born on this day 217 years ago.

John Venn was born on this day 188 years ago.

Properties of the number 48808:

48808 = 23 × 6101 is the 43789th composite number and is not squarefree.
48808 has 2 distinct prime factors, 8 divisors, 13 antidivisors and 24400 totatives.
48808 has a triangular digit sum 28 in base 10.
48808 = 122032 - 122012 = 61032 - 60992 is the difference of 2 nonnegative squares in 2 ways.
48808 is the sum of 2 positive triangular numbers.
48808 is the difference of 2 positive pentagonal numbers in 2 ways.
48808 = 982 + 1982 is the sum of 2 positive squares in 1 way.
48808 = 82 + 1502 + 1622 is the sum of 3 positive squares.
488082 = 296002 + 388082 is the sum of 2 positive squares in 1 way.
488082 is the sum of 3 positive squares.
48808 is a proper divisor of 172310 - 1.
48808 is palindromic in (at least) the following bases: 47, -57, -59, and -80.
48808 in base 47 = M4M and consists of only the digits '4' and 'M'.

The number 48808 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A175103: Integers n such that 17+30*n are terms in A172456.
A248488: Number of length n+5 0..7 arrays with some three disjoint pairs in each consecutive six terms having the same sum.
A248493: Number of length 4+5 0..n arrays with some three disjoint pairs in each consecutive six terms having the same sum

Wednesday, August 3, 2022

Number of the day: 124586

Properties of the number 124586:

124586 = 2 × 7 × 11 × 809 is the 112885th composite number and is squarefree.
124586 has 4 distinct prime factors, 16 divisors, 15 antidivisors and 48480 totatives.
124586 has an emirpimes digit sum 26 in base 10.
Reversing the decimal digits of 124586 results in a semiprime.
124586 is the difference of 2 positive pentagonal numbers in 3 ways.
124586 = 92 + 642 + 3472 is the sum of 3 positive squares.
1245862 = 431202 + 1168862 is the sum of 2 positive squares in 1 way.
1245862 is the sum of 3 positive squares.
124586 is a proper divisor of 49120 - 1.
124586 = '12458' + '6' is the concatenation of 2 semiprime numbers.
124586 is palindromic in (at least) the following bases: 52, 78, and -76.
124586 in base 3 = 20022220022 and consists of only the digits '0' and '2'.
124586 in base 52 = k3k and consists of only the digits '3' and 'k'.
124586 in base 58 = b22 and consists of only the digits '2' and 'b'.

The number 124586 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequence (among others):

Sequence number and description below are taken from OEIS.
A351716: Starts of runs of 3 consecutive Lucas-Niven numbers (A351714).