25641

Appears in sequences

• Positive numbers k such that k and 2*k are anagrams in base 7 (written in base 7).at n=8A023068
• a(n) is the least positive integer such that nextprime(a(n)^n) - prevprime(a(n)^n) = 4.at n=26A090125
• Number of Pythagorean quadruples mod n; i.e., number of solutions to w^2 + x^2 + y^2 = z^2 mod n.at n=32A096018
• Numbers k such that the central binomial coefficient C(2k,k) is divisible by k^2.at n=38A121943
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, 0, 1), (-1, 1, 1), (1, -1, 1), (1, 0, -1), (1, 1, 0)}.at n=8A149494
• Triangle read by rows: T(n,k) = number of partitions of [1..k] into n nonempty clumps of sizes 1, 2, 3, 4, 5 or 6 (n >= 0, 0 <= k <= 6n).at n=31A151359
• The triangle in A151359 read by rows downwards.at n=69A151511
• Numerator of Euler(n, 5/31).at n=3A157624
• Numbers n such that n^6 + 272 is prime.at n=37A161998
• Decimal form of the period of 1/n for n such that gcd(n,10)=1. Leading zeros are suppressed.at n=14A178505
• a(n) = n*(3*n^2 - 5*n + 3).at n=21A226450
• Table (read by rows) of the natural numbers (in ascending order) whose reciprocals have only periodic decimals of length k.at n=68A226477
• Numbers n dividing every cyclic permutation of n^4.at n=30A242740
• 4th-largest term in n-th row of Stern's diatomic triangle A002487.at n=18A244474
• Numbers m such that the result of prepending a zero digit to m, removing the least significant digit D, and prepending D, is divisible by m.at n=42A256005
• Numbers n such that A002088(n) is a triangular number.at n=16A276645
• Numbers k satisfying gcd(k^2, sigma(k^2)) > sigma(k), where sigma is the sum-of-divisors function.at n=17A322154
• Positive integers n (with k digits) such that if a positive integer m with k+1 digits is divisible by n, then all the rotations of m are divisible by n.at n=13A360423
• a(n) = Sum_{k=1..n} sigma_2( n/gcd(k,n) ).at n=32A372226
• Expansion of e.g.f. exp(g^3 - 1), where g = 1+x*g^4 is the g.f. of A002293.at n=4A391549