a(n) = Sum_{k=0..n} (4*k+1) * binomial(2*n+2*k+1,n-k)/(2*n+2*k+1).

A390527

a(n) = Sum_{k=0..n} (4*k+1) * binomial(2*n+2*k+1,n-k)/(2*n+2*k+1).

Terms

    a(0) =1a(1) =2a(2) =8a(3) =35a(4) =157a(5) =712a(6) =3248a(7) =14869a(8) =68222a(9) =313487a(10) =1441999a(11) =6637879a(12) =30572032a(13) =140860379a(14) =649202036a(15) =2992721902a(16) =13798302512a(17) =63626933527a(18) =293426802548

External references