G.f.: A(x,y) = exp( Sum_{n>=1} [Sum_{k=0..n} C(n,k)^4*y^k] * x^n/n ) = Sum_{n>=0,k=0..n} T(n,k)*x^n*y^k, as a triangle of coefficients T(n,k) read by rows.

A181144

G.f.: A(x,y) = exp( Sum_{n>=1} [Sum_{k=0..n} C(n,k)^4*y^k] * x^n/n ) = Sum_{n>=0,k=0..n} T(n,k)*x^n*y^k, as a triangle of coefficients T(n,k) read by rows.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =9a(5) =1a(6) =1a(7) =36a(8) =36a(9) =1a(10) =1a(11) =100a(12) =419a(13) =100a(14) =1a(15) =1a(16) =225a(17) =2699a(18) =2699a(19) =225a(20) =1a(21) =1a(22) =441a(23) =12138a(24) =35052a(25) =12138a(26) =441a(27) =1a(28) =1a(29) =784

External references