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A002599
A generalized partition function.
(Formerly M4106 N1703)
1
1, 6, 15, 19, 24, 42, 73, 127, 208, 337, 528, 827, 1263, 1902, 2819, 4133, 5986, 8578, 12146, 17057, 23711, 32708, 44726, 60713, 81800, 109468, 145526, 192288, 252521, 329792, 428316, 553478, 711596, 910563, 1159790, 1470798, 1857286, 2335838
OFFSET
1,2
REFERENCES
Hansraj Gupta, A generalization of the partition function. Proc. Nat. Inst. Sci. India 17 (1951), 231-238.
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
Hansraj Gupta, A generalization of the partition function, Proc. Nat. Inst. Sci. India 17 (1951), 231-238. [Annotated scanned copy]
MAPLE
J:= m-> product((1-x^j)^(-j), j=1..m): a:= t-> coeff(series(J(min(5, t)), x, 1+max(5, t)), x, max(5, t)): seq(a(n), n=1..40); # Alois P. Heinz, Jul 20 2009
MATHEMATICA
J[m_] := Product[(1-x^j)^-j, {j, 1, m}]; a[t_] := SeriesCoefficient[J[Min[5, t]], {x, 0, Max[5, t]}]; Table[a[n], {n, 1, 40}] (* Jean-François Alcover, Mar 13 2014, after Alois P. Heinz *)
CROSSREFS
Sequence in context: A362141 A044058 A105139 * A001484 A217480 A335417
KEYWORD
nonn
EXTENSIONS
More terms from Alois P. Heinz, Jul 20 2009
STATUS
approved