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A128056 Hankel transform of A128057. 5
1, -3, -6, 28, 56, -288, -576, 3008, 6016, -31488, -62976, 329728, 659456, -3452928, -6905856, 36159488, 72318976, -378667008, -757334016, 3965452288, 7930904576, -41526755328, -83053510656, 434873827328 (list; graph; refs; listen; history; text; internal format)
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 A220823

Adjacent sequences:  A128053 A128054 A128055 * A128057 A128058 A128059

KEYWORD

easy,sign

AUTHOR

Paul Barry, Feb 13 2007

STATUS

approved

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Last modified January 26 14:08 EST 2020. Contains 331280 sequences. (Running on oeis4.)