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A304883 Expansion of Product_{k>=1} 1/(1-x^(3*k-1)) * Product_{k>=1} 1/(1-x^(6*k-5)). 1
1, 1, 2, 2, 3, 4, 5, 7, 9, 11, 14, 17, 21, 26, 32, 39, 47, 56, 67, 80, 95, 113, 133, 156, 183, 214, 250, 291, 338, 391, 452, 521, 600, 690, 791, 906, 1035, 1181, 1346, 1532, 1741, 1975, 2238, 2532, 2862, 3231, 3643, 4103, 4615, 5186, 5822, 6529, 7315, 8187, 9154 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
LINKS
Sylvie Corteel, Carla D. Savage, and Andrew V. Sills. F. Beukers, Lecture hall sequences, q-series, and asymmetric partition identities, In Alladi K., Garvan F. (eds) Partitions, q-Series, and Modular Forms pp 53-68. Developments in Mathematics, vol 23. Springer, New York, NY.
FORMULA
G.f.: Sum_{j>=0} x^(j*(3*j+1)/2)*(Product_{k=1..j} (1-x^(6*k-2)))/(Product_{k=1..3*j+1} (1-x^k)).
a(n) ~ exp(Pi*sqrt(n/3)) * Gamma(1/3) / (4 * 3^(1/3) * Pi^(2/3) * n^(2/3)). - Vaclav Kotesovec, May 21 2018
MAPLE
seq(coeff(series(mul(1/(1-x^(3*k-1)), k=1..n)*mul(1/(1-x^(6*k-5)), k=1..n), x, 70), x, n), n=0..60); # Muniru A Asiru, May 21 2018
MATHEMATICA
CoefficientList[ Series[ Product[1/(1 - x^(3k -1)), {k, 18}]*Product[1/(1 - x^(6k -5)), {k, 9}], {x, 0, 54}], x] (* Robert G. Wilson v, May 20 2018 *)
CROSSREFS
Sequence in context: A317177 A326491 A266748 * A280663 A052816 A122130
KEYWORD
nonn
AUTHOR
Seiichi Manyama, May 20 2018
STATUS
approved

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Last modified June 7 09:52 EDT 2024. Contains 373162 sequences. (Running on oeis4.)