22752

Appears in sequences

• Numbers k such that sigma (x) = k has exactly 12 solutions.at n=25A060676
• a(n) = 9*(n-2)^2*(n^2-2*n-1)/2.at n=8A064199
• a(n) = Z(S_m; sigma[1](n), sigma[2](n),..., sigma[m](n)) where Z(S_m; x_1,x_2,...,x_m) is the cycle index of the symmetric group S_m and sigma[k](n) is the sum of k-th powers of divisors of n; m=3.at n=21A068020
• Multiples of 6 with only prime digits (2, 3, 5 and 7).at n=32A077535
• a(n) = 2*n^3 - 3*n^2 + 5.at n=23A152064
• Sums of 2 successive primes s = prime(m) + prime(m+1) such that all digits of s are primes.at n=18A173719
• Expansion of 1 / (1-4*x^2-3*x^3). (4,3)-Padovan sequence.at n=13A176737
• Triangle T(n,k) for solving differential equation A'(x)=G(A(x)), G(0)!=0.at n=35A190015
• Number of 2 X 2 matrices having all terms in {-n,...,0,...,n} and determinant n.at n=30A211140
• Numbers n such that there exists an x!=n that makes {x,x,n} an amicable multiset.at n=4A259303
• Numbers that belong to at least one amicable multiset.at n=42A259307
• a(n) = a(n-2) + a(n-3) for n >= 3, with a(0) = a(1) = 2, a(2) = 1.at n=35A276477
• G.f. A(x) satisfies: (1 + x)/(1 - x) = A(x)*A(x^2)^2*A(x^3)^3*A(x^4)^4* ... *A(x^k)^k* ...at n=31A307659
• Numbers k such that 301*2^k+1 is prime.at n=11A322915
• Numbers k that have at least two different representations as the product of a number and of its decimal digits.at n=16A336944