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A160636 Hankel transform of A114464. 1
1, 0, -1, -2, -8, 0, 128, 1024, 16384, 0, -4194304, -134217728, -8589934592, 0, 35184372088832, 4503599627370496, 1152921504606846976, 0, -75557863725914323419136, -38685626227668133590597632 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

The absolute value sequence has general term 2^floor(C(n,2)/2)*(3/4-cos(pi*n/4)-sin(pi*n/2)/2).

Hankel transform of A114464(n+1) is A160637.

LINKS

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

FORMULA

a(n)=2^floor(C(n,2)/2)*((sqrt(2)/2-1/2)sin(3*pi*n/4)+pi/4)+(sqrt(2)/2+1/2)cos(pi*n/4+pi/4)).

CROSSREFS

Sequence in context: A028256 A209455 A288873 * A282626 A206712 A200704

Adjacent sequences:  A160633 A160634 A160635 * A160637 A160638 A160639

KEYWORD

easy,sign

AUTHOR

Paul Barry, May 21 2009

STATUS

approved

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Last modified August 21 15:56 EDT 2017. Contains 290890 sequences.