92960

Appears in sequences

• Smaller member of an infinitary amicable pair.at n=21A126169
• Indices k such that 9 plus the k-th triangular number is a perfect square.at n=12A154142
• G.f. satisfies A(x) = G(x/(1-x)^3) where G(x) = 1 + x*G(x)^3 is the g.f. of A001764.at n=7A213282
• Let x be the sum of the divisors d_i of k such that d_i | sigma(k). Sequence lists the numbers k for which x^2 = sigma(k).at n=7A284283
• E.g.f. satisfies A(x) = x * exp(x + 3 * A(x)).at n=5A360482
• Triangle read by rows: T(n, k) = 3^n*Sum_{j=0..k} (-1)^(k - j)*binomial(k, j) * Pochhammer(j/3, n).at n=23A371076
• Square array T(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where T(n,0) = 0^n and T(n,k) = k * Sum_{r=0..n} binomial(n,r) * binomial(n+2*r+k,n)/(n+2*r+k) for k > 0.at n=51A378236