38690

Appears in sequences

• Generalized Catalan Numbers x^3*A(x)^2 -(1-x+x^3+x^4)*A(x) + 1 =0.at n=21A023433
• Numbers k such that 5*R_k + 4 is prime, where R_k = 11...1 is the repunit (A002275) of length k.at n=13A099418
• a(n) = (n^2 + 1) * (2*n - 1).at n=26A290631