G.f. A(x) satisfies: 4^n/2 = Sum_{k=0..n} [x^k]A(x)^n and also satisfies: ((4+z)^n + z^n)/2 = Sum_{k=0..n} [x^k](A(x)+z*x)^n for all z, where [x^k]A(x)^n denotes the coefficient of x^k in A(x)^n.
A100240
G.f. A(x) satisfies: 4^n/2 = Sum_{k=0..n} [x^k]A(x)^n and also satisfies: ((4+z)^n + z^n)/2 = Sum_{k=0..n} [x^k](A(x)+z*x)^n for all z, where [x^k]A(x)^n denotes the coefficient of x^k in A(x)^n.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =2a(4) =0a(5) =-4a(6) =-6a(7) =2a(8) =22a(9) =30a(10) =-26a(11) =-154a(12) =-172a(13) =288a(14) =1190a(15) =990a(16) =-3040a(17) =-9620a(18) =-4970a(19) =31350a(20) =79120a(21) =12580a(22) =-318210a(23) =-649610a(24) =174150a(25) =3185686a(26) =5233514a(27) =-4273078a(28) =-31452228a(29) =-40495600
External references
- oeis: A100240