G.f. A(x) satisfies 7*x = Sum_{n=-oo..+oo} (-1)^n * x^(7*n) * (A(x) + x^n)^(7*n) with A(0) = 1.
A380684
G.f. A(x) satisfies 7*x = Sum_{n=-oo..+oo} (-1)^n * x^(7*n) * (A(x) + x^n)^(7*n) with A(0) = 1.
Terms
- a(0) =1a(1) =4a(2) =20a(3) =110a(4) =638a(5) =3828a(6) =23515a(7) =146974a(8) =930940a(9) =5959555a(10) =38485153a(11) =250361331a(12) =1639087576a(13) =10791380549a(14) =71409038308a(15) =474737253262
External references
- oeis: A380684