Triangle read by rows in which row n >= 1 gives coefficients in expansion of the polynomial Sum_{k=1..n} (1/n)*binomial(n,k)*binomial(n,k-1)*x^(2k)*(1+x)^(2n-2k) / x^2 in powers of x.

A086873

Triangle read by rows in which row n >= 1 gives coefficients in expansion of the polynomial Sum_{k=1..n} (1/n)*binomial(n,k)*binomial(n,k-1)*x^(2k)*(1+x)^(2n-2k) / x^2 in powers of x.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =2a(4) =1a(5) =4a(6) =9a(7) =10a(8) =5a(9) =1a(10) =6a(11) =21a(12) =44a(13) =57a(14) =42a(15) =14a(16) =1a(17) =8a(18) =38a(19) =116a(20) =240a(21) =336a(22) =308a(23) =168a(24) =42a(25) =1a(26) =10a(27) =60a(28) =240a(29) =680

External references