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A174618 For n odd a(n) = a(n-2) + a(n-3), for n even a(n) = a(n-2) + a(n-5); with a(1) = 0, a(2) = 1. 1
0, 1, 0, 1, 1, 1, 2, 1, 3, 2, 4, 4, 6, 7, 10, 11, 17, 17, 28, 27, 45, 44, 72, 72, 116, 117, 188, 189, 305, 305, 494, 493, 799, 798, 1292, 1292, 2090, 2091, 3382, 3383, 5473, 5473, 8856, 8855, 14329, 14328, 23184, 23184, 37512, 37513, 60696 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,7

COMMENTS

Combination a(2n)=A005252(n-1) and a(2n+1)=A024490(n). Consecutive pairs add up to A000045 and subtract to A010892. If a(1)= 1 formula gives: A103609.

LINKS

Table of n, a(n) for n=1..51.

Index entries for linear recurrences with constant coefficients, signature (0,2,0,-1,0,0,0,1).

FORMULA

G.f.: -x^2*(1-x^2+x^3) / ( (x^4-x^2+1)*(x^4+x^2-1) ). - R. J. Mathar, Jan 27 2011

EXAMPLE

As consecutive pairs:

(0,1),(0,1),(1,1),(2,1),(3,2),(4,4),...

CROSSREFS

Cf. A005252, A024490, A000045, A010892.

Sequence in context: A239243 A206738 A282971 * A144241 A094173 A214370

Adjacent sequences:  A174615 A174616 A174617 * A174619 A174620 A174621

KEYWORD

nonn,easy

AUTHOR

Mark Dols, Mar 23 2010

STATUS

approved

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Last modified February 23 21:23 EST 2018. Contains 299588 sequences. (Running on oeis4.)