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, 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

T. D. Noe, Table of n, a(n) for n = 0..1000

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]

Index entries for linear recurrences with constant coefficients, signature (9, -33, 63, -66, 36, -8).

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

Adjacent sequences: A001991 A001992 A001993 * A001995 A001996 A001997

Keyword

nonn,easy

Author

N. J. A. Sloane

Extensions

More terms from James A. Sellers, Feb 09 2000

Status

approved