a(n) = S2(n,1), where S2(n, t) = Sum_{k=0..n} k^t *(Sum_{j=0..k} binomial(n,j))^2.

A089664

a(n) = S2(n,1), where S2(n, t) = Sum_{k=0..n} k^t *(Sum_{j=0..k} binomial(n,j))^2.

Terms

    a(0) =0a(1) =4a(2) =41a(3) =306a(4) =1966a(5) =11540a(6) =63726a(7) =336700a(8) =1720364a(9) =8562024a(10) =41718190a(11) =199753004a(12) =942561636a(13) =4392660376a(14) =20253510956a(15) =92519626200a(16) =419201709976

External references