255800

Appears in sequences

• Starting from the standard 12 against 12 starting position in checkers, the sequence gives the number of distinct positions that can arise after n moves.at n=9A133047
• G.f. A(x) satisfies: [x^n] A(x)^(n+1) = (n+1)^2 * [x^(n-1)] A(x)^(n+1) for n >= 1 with A'(0) = 1.at n=5A323693