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A074139
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Number of divisors of A036035(n,k).
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18
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1, 2, 3, 4, 4, 6, 8, 5, 8, 9, 12, 16, 6, 10, 12, 16, 18, 24, 32, 7, 12, 15, 16, 20, 24, 27, 32, 36, 48, 64, 8, 14, 18, 20, 24, 30, 32, 36, 40, 48, 54, 64, 72, 96, 128, 9, 16, 21, 24, 25, 28, 36, 40, 45, 48, 48, 60, 64, 72, 81, 80, 96, 108, 128, 144, 192, 256
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OFFSET
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0,2
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LINKS
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Alois P. Heinz, Rows n = 0..30, flattened
Byungchul Cha et al., An Investigation on Partitions with Equal Products, arXiv:1811.07451 [math.NT], 2018.
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FORMULA
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T(n,k) = A000005(A036035(n,k)). - R. J. Mathar, Aug 28 2018
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EXAMPLE
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Express A036035(n,k) by its prime signature; add one to each exponent, then multiply: 180 = (2^2)*(3^2)*(5^1) therefore the number of divisors is (2+1)*(2+1)*(1+1)= 18
From Michel Marcus, Nov 11 2015: (Start)
As an irregular triangle, whose n-th row has A000041(n) terms, sequence begins:
1;
2;
3, 4;
4, 6, 8;
5, 8, 9, 12, 16;
6, 10, 12, 16, 18, 24, 32;
...
(End)
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PROG
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(PARI) tabf(nn) = {for (n=1, nn, forpart(p=n, print1(prod(k=1, #p, (1+p[k])), ", ")); print(); ); } \\ Michel Marcus, Nov 11 2015
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CROSSREFS
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Row sums give A074141.
Cf. A036035, A074140.
Sequence in context: A007896 A325682 A241088 * A238963 A331527 A326575
Adjacent sequences: A074136 A074137 A074138 * A074140 A074141 A074142
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KEYWORD
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nonn,look,tabf
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AUTHOR
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Amarnath Murthy, Aug 28 2002
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EXTENSIONS
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More terms from Alford Arnold, Sep 17 2002
Term ordering corrected by Alois P. Heinz, Aug 21 2019
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STATUS
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approved
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