1677312

Appears in sequences

• Numbers k such that rad(k)^2 divides sigma(k).at n=29A173615
• Expansion of 1/(1-2*x^2-4*x^3). (2,4)-Padovan sequence.at n=22A176739
• Triangle read by rows: T(n,k) = t(n-k, k); t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 4*x + 2.at n=37A257612
• Triangle read by rows: T(n,k) = t(n-k, k); t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 4*x + 2.at n=43A257612