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A226509
Expansion of (3-2*x)/(1-x-x^3)+x/(1-x)^2+x/(1-x^2).
1
3, 3, 3, 8, 9, 12, 16, 23, 29, 41, 56, 79, 110, 158, 225, 325, 469, 682, 991, 1446, 2110, 3085, 4511, 6603, 9666, 14157, 20736, 30380, 44511, 65223, 95575, 140060, 205253, 300800, 440828, 646051, 946817, 1387613, 2033628, 2980411
OFFSET
0,1
REFERENCES
Z. Skupien, Sums of Powered Characteristic Roots Count Distance-Independent Circular Sets, Discussiones Mathematicae Graph Theory. Volume 33, Issue 1, Pages 217-229, ISSN (Print) 2083-5892, DOI: 10.7151/dmgt.1658, April 2013.
FORMULA
a(n) = A137726(n), for n>2 and a(0) = a(1) = a(2) = 3. [Bruno Berselli, Jun 17 2013]
MATHEMATICA
CoefficientList[Series[(3 - 2 x) / (1 - x - x^3) + x / (1 - x)^2 + x / (1 - x^2), {x, 0, 40}], x] (* Vincenzo Librandi, Jun 19 2013 *)
CROSSREFS
Sequence in context: A029628 A346159 A241739 * A329694 A183389 A275530
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Jun 11 2013
STATUS
approved