A134185 - OEIS

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A134185

Hankel transform of a transform of the central binomial coefficients A001405.

1, 2, 0, -8, -32, -256, 0, 16384, 262144, 8388608, 0, -8589934592, -549755813888, -70368744177664, 0, 1152921504606846976, 295147905179352825856, 151115727451828646838272, 0, -39614081257132168796771975168

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,2

COMMENTS

Hankel transform of A134184.

LINKS

Table of n, a(n) for n=0..19.

FORMULA

a(n) = ((1/2 - 1/sqrt(2))*cos(3*Pi*n/4) + (1/2 + 1/sqrt(2))*cos(Pi*n/4))*2^ceiling(binomial(n+1,2)/2).

CROSSREFS

Cf. A001405, A134184.

Sequence in context: A062134 A002909 A118437 * A013489 A013342 A109589

Adjacent sequences: A134182 A134183 A134184 * A134186 A134187 A134188

KEYWORD

easy,sign

AUTHOR

Paul Barry, Oct 11 2007

STATUS

approved