121810

Appears in sequences

• Coefficient of x^4 in expansion of (1+x+x^2)^n.at n=38A005712
• Index in A092243 where -n first appears.at n=22A269738
• Expansion of 1/(1 - x^2 - x^3/(1 - x^5 - x^7/(1 - x^11 - x^13/(1 - ... - x^prime(2*k)/(1 - x^prime(2*k+1) - ...))))), a continued fraction.at n=38A292802
• a(n) = trinomial(2*n, 4) = (1/6)*n*(2*n - 1)*(2*n^2 + 7*n - 3).at n=20A302710