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A166445 Hankel transform of A025276. 1
1, 0, -1, 1, 3, 0, -3, 1, 5, 0, -5, 1, 7, 0, -7, 1, 9, 0, -9, 1, 11, 0, -11, 1, 13, 0, -13, 1, 15, 0, -15, 1, 17, 0, -17, 1, 19, 0, -19, 1, 21, 0, -21, 1, 23, 0, -23, 1, 25, 0, -25, 1, 27, 0, -27, 1, 29, 0, -29, 1, 31, 0, -31, 1, 33, 0, -33, 1, 35, 0, -35, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

LINKS

Table of n, a(n) for n=0..71.

Index entries for linear recurrences with constant coefficients, signature (1,-2,2,-1,1).

FORMULA

G.f.: (1-x+x^2+x^4)/((1-x)(1+x^2)^2).

n = (1/2)*(1 + Cos[(n*Pi)/2] + n*Sin[(n*Pi)/2]). - Harvey P. Dale, Nov 21 2014

MATHEMATICA

LinearRecurrence[{1, -2, 2, -1, 1}, {1, 0, -1, 1, 3}, 80] (* Harvey P. Dale, Nov 21 2014 *)

CROSSREFS

Sequence in context: A318505 A237595 A322575 * A298082 A085919 A105824

Adjacent sequences:  A166442 A166443 A166444 * A166446 A166447 A166448

KEYWORD

easy,sign

AUTHOR

Paul Barry, Oct 13 2009

EXTENSIONS

More terms from Harvey P. Dale, Nov 21 2014

STATUS

approved

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Last modified July 12 22:46 EDT 2020. Contains 335669 sequences. (Running on oeis4.)