Expansion of (g/(1 - x*g^2))^2, where g = 1+x*g^4 is the g.f. of A002293.
A391199
Expansion of (g/(1 - x*g^2))^2, where g = 1+x*g^4 is the g.f. of A002293.
Terms
- a(0) =1a(1) =4a(2) =20a(3) =118a(4) =774a(5) =5444a(6) =40191a(7) =307358a(8) =2414049a(9) =19359908a(10) =157879092a(11) =1305263820a(12) =10915318617a(13) =92167342092a(14) =784730638796
External references
- oeis: A391199