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A001994
Expansion of 1/((1-x^2)*(1-x^4)^2*(1-x^6)*(1-x^8)*(1-x^10)) (even powers only).
(Formerly M2348 N0927)
1
1, 1, 3, 4, 8, 11, 18, 24, 36, 47, 66, 84, 113, 141, 183, 225, 284, 344, 425, 508, 617, 729, 872, 1020, 1205, 1397, 1632, 1877, 2172, 2480, 2846, 3228, 3677, 4146, 4691, 5261, 5917, 6603, 7386, 8205, 9133, 10103, 11195, 12336, 13613, 14947, 16431, 17981, 19697
OFFSET
0,3
REFERENCES
A. Cayley, Calculation of the minimum N.G.F. of the binary seventhic, Collected Mathematical Papers. Vols. 1-13, Cambridge Univ. Press, London, 1889-1897, Vol. 10, p. 408-419.
N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
A. Cayley, Calculation of the minimum N.G.F. of the binary seventhic, Collected Mathematical Papers. Vols. 1-13, Cambridge Univ. Press, London, 1889-1897, Vol. 10, p. 408-419. [Annotated scanned copy]
MATHEMATICA
nn = 202; t = CoefficientList[Series[1/((1 - x^2)*(1 - x^4)^2*(1 - x^6)*(1 - x^8)*(1 - x^10)), {x, 0, nn}], x]; t = Take[t, {1, nn, 2}]
CROSSREFS
Cf. A001996.
Sequence in context: A236453 A099108 A208971 * A212544 A349801 A320787
KEYWORD
nonn,easy
EXTENSIONS
More terms from James A. Sellers, Feb 09 2000
STATUS
approved