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A030272
Number of partitions of n^3 into distinct cubes.
18
1, 1, 1, 1, 1, 1, 2, 1, 1, 3, 1, 1, 3, 4, 6, 6, 7, 6, 20, 18, 21, 42, 55, 52, 80, 126, 140, 201, 323, 361, 600, 626, 938, 1387, 1648, 2310, 3620, 4575, 5495, 9278, 11239, 14229, 23406, 28780, 38218, 53987, 73114, 87568, 134007, 181986, 233004, 348230, 432184
OFFSET
0,7
LINKS
FORMULA
a(n) = [x^(n^3)] Product_{k>=1} (1 + x^(k^3)). - Ilya Gutkovskiy, Apr 13 2017
a(n) = A279329(n^3). - Vaclav Kotesovec, May 06 2019
a(n) ~ exp(2^(7/4) * 3^(-3/2) * ((2^(1/3)-1) * Gamma(1/3) * Zeta(4/3))^(3/4) * n^(3/4)) * ((2^(1/3)-1) * Gamma(1/3) * Zeta(4/3))^(3/8) / (2^(17/8) * 3^(1/4) * sqrt(Pi) * n^(21/8)). - Vaclav Kotesovec, May 06 2019
EXAMPLE
a(6) = 2: [27,64,125], [216].
a(9) = 3: [1,27,64,125,512], [1,216,512], [729].
MATHEMATICA
nmax = 50; poly = ConstantArray[0, nmax^3 + 1]; poly[[1]] = 1; poly[[2]] = 1; Do[Do[poly[[j + 1]] += poly[[j - k^3 + 1]], {j, nmax^3, k^3, -1}]; , {k, 2, nmax}]; Table[poly[[1 + n^3]], {n, 0, nmax}] (* Vaclav Kotesovec, Sep 19 2020 *)
PROG
(PARI) apply( A030272(n)=A279329(n^3), [0..30]) \\ M. F. Hasler, Jan 05 2020
CROSSREFS
KEYWORD
nonn
EXTENSIONS
a(0)=1 prepended by Ilya Gutkovskiy, Apr 13 2017
STATUS
approved