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A074139
Number of divisors of A036035(n,k).
19
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
OFFSET
0,2
LINKS
Byungchul Cha et al., An Investigation on Partitions with Equal Products, arXiv:1811.07451 [math.NT], 2018.
FORMULA
T(n,k) = A000005(A036035(n,k)). - R. J. Mathar, Aug 28 2018
EXAMPLE
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)
PROG
(PARI) tabf(nn) = {for (n=1, nn, forpart(p=n, print1(prod(k=1, #p, (1+p[k])), ", ")); print(); ); } \\ Michel Marcus, Nov 11 2015
CROSSREFS
Row sums give A074141.
Sequence in context: A351006 A325682 A241088 * A355026 A238963 A342940
KEYWORD
nonn,look,tabf
AUTHOR
Amarnath Murthy, Aug 28 2002
EXTENSIONS
More terms from Alford Arnold, Sep 17 2002
Term ordering corrected by Alois P. Heinz, Aug 21 2019
STATUS
approved