A128056 Hankel transform of A128057.

1, -3, -6, 28, 56, -288, -576, 3008, 6016, -31488, -62976, 329728, 659456, -3452928, -6905856, 36159488, 72318976, -378667008, -757334016, 3965452288, 7930904576, -41526755328, -83053510656, 434873827328

Offset

0,2

Comments

a(n)=2^A128054(n)*A128053(n). Hankel transform of A128058.

Links

Table of n, a(n) for n=0..23.

Formula

a(n)=A128055(n)*((cos(pi*n/2)-sin(pi*n/2))((F(n-1)+F(n+1))(5/6-cos(pi*n/3)/3)(1+(-1)^n)/2 +(F(n)+F(n+2))(5/6-cos(pi*(n+1)/3)/3)(1-(-1)^n)/2)).

Empirical g.f.: -(2*x-1)*(4*x^2-x+1) / (16*x^4+12*x^2+1). - Colin Barker, Jun 27 2013

Crossrefs

Sequence in context: A076711 A075088 A102428 * A068808 A068133 A377706

Adjacent sequences: A128053 A128054 A128055 * A128057 A128058 A128059

Keyword

easy,sign

Author

Paul Barry, Feb 13 2007

Status

approved