5719519850

Appears in sequences

• a(n) = (binomial(4*n, 2*n) + binomial(2*n, n)^2)/2.at n=9A036910
• a(n) = Sum_{k=0..9} binomial(18,k)*binomial(n,k).at n=18A247614
• a(n) = Sum_{k=0..floor(n/2)} binomial(n, k)^2.at n=18A277247