50607domain: NAppears in sequencesa(n) = 625*n^2 - 2*n.at n=8A158373The first of 33 consecutive positive integers the sum of the squares of which is a square.at n=12A269449Expansion of g.f. A(x) satisfying 1 = Sum_{n>=0} (-1)^n * x^n * A(x)^(2*n+1) * Product_{k=1..n} (1 + x^k).at n=9A366231