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A025820 Expansion of 1/((1-x^2)(1-x^7)(1-x^12)). 0
1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 2, 1, 3, 1, 3, 1, 3, 2, 3, 3, 3, 3, 4, 3, 5, 3, 6, 3, 6, 4, 6, 5, 6, 6, 7, 6, 8, 6, 9, 6, 10, 7, 10, 8, 10, 9, 11, 10, 12, 10, 13, 10, 14, 11, 15, 12, 15, 13, 16, 14, 17, 15, 18, 15, 19, 16, 20 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,13

LINKS

Table of n, a(n) for n=0..68.

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

FORMULA

a(0)=1, a(1)=0, a(2)=1, a(3)=0, a(4)=1, a(5)=0, a(6)=1, a(7)=1, a(8)=1, a(9)=1, a(10)=1, a(11)=1, a(12)=2, a(13)=1, a(14)=3, a(15)=1, a(16)=3, a(17)=1, a(18)=3, a(19)=2, a(20)=3, a(n)=a(n-2)+a(n-7)-a(n-9)+ a(n-12)- a(n-14)- a(n-19)+a(n-21). - Harvey P. Dale, Oct 14 2014

MATHEMATICA

CoefficientList[Series[1/((1-x^2)(1-x^7)(1-x^12)), {x, 0, 120}], x] (* or *) LinearRecurrence[{0, 1, 0, 0, 0, 0, 1, 0, -1, 0, 0, 1, 0, -1, 0, 0, 0, 0, -1, 0, 1}, {1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 2, 1, 3, 1, 3, 1, 3, 2, 3}, 120] (* Harvey P. Dale, Oct 14 2014 *)

CROSSREFS

Sequence in context: A152188 A239930 A226859 * A109704 A073407 A049994

Adjacent sequences:  A025817 A025818 A025819 * A025821 A025822 A025823

KEYWORD

nonn

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified September 26 05:07 EDT 2021. Contains 347664 sequences. (Running on oeis4.)