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 A279951 Expansion of Product_{k>=1} 1/(1 - x^((k*(k+1)/2)^2)). 0
 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 6, 6, 6, 6, 6, 6, 6, 6, 6, 8, 8, 8, 8, 8, 8, 8, 8, 8, 10, 10, 10, 10, 10, 10, 10, 10, 10, 12, 12, 12, 12, 12, 12, 12, 12, 12, 15, 15, 15, 15, 15, 15, 15, 15, 15, 18, 18, 18, 18, 18, 18, 18, 18, 18, 21, 21, 21, 21, 21, 21, 21, 21, 21, 24, 25, 25, 25, 25, 25, 25 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,10 COMMENTS Number of partitions of n into nonzero squared triangular numbers (A000537). LINKS M. Bernstein and N. J. A. Sloane, Some canonical sequences of integers, Linear Alg. Applications, 226-228 (1995), 57-72; erratum 320 (2000), 210. [Link to arXiv version] M. Bernstein and N. J. A. Sloane, Some canonical sequences of integers, Linear Alg. Applications, 226-228 (1995), 57-72; erratum 320 (2000), 210. [Link to Lin. Alg. Applic. version together with omitted figures] Wikipedia, Squared triangular number FORMULA G.f.: Product_{k>=1} 1/(1 - x^((k*(k+1)/2)^2)). EXAMPLE a(10) = 2 because we have [9, 1] and [1, 1, 1, 1, 1, 1, 1, 1, 1, 1]. MATHEMATICA nmax = 105; CoefficientList[Series[Product[1/(1 - x^((k (k + 1)/2)^2)), {k, 1, nmax}], {x, 0, nmax}], x] CROSSREFS Cf. A000537, A007294, A068980. Sequence in context: A111857 A133879 A054898 * A279224 A167383 A167661 Adjacent sequences:  A279948 A279949 A279950 * A279952 A279953 A279954 KEYWORD nonn AUTHOR Ilya Gutkovskiy, Dec 23 2016 STATUS approved

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Last modified December 3 05:29 EST 2020. Contains 338899 sequences. (Running on oeis4.)