3256957317

Appears in sequences

• a(n) = Sum_{k=0..n-1} binomial(n,k+1) * binomial(n+k,k).at n=14A002002
• a(n) = T([n/2],[(n+1)/2]), where T = Delannoy triangle (A008288).at n=27A026003
• a(n) = Hypergeometric([-n, n], [1], 2).at n=14A182626