G.f. A(x) satisfies: [x^n] A(x) * (1+x)^(n*(n-1)/2) = [x^n] (1+x)^(n*(n+1)/2) for n >= 0.
A304403
G.f. A(x) satisfies: [x^n] A(x) * (1+x)^(n*(n-1)/2) = [x^n] (1+x)^(n*(n+1)/2) for n >= 0.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =10a(4) =85a(5) =1001a(6) =15036a(7) =273932a(8) =5858560a(9) =143735650a(10) =3976623010a(11) =122427035732
External references
- oeis: A304403