

A074139


Number of divisors of A036035(n,k).


18



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

0,2


LINKS

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.


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 nth 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.
Cf. A036035, A074140.
Sequence in context: A007896 A325682 A241088 * A238963 A331527 A326575
Adjacent sequences: A074136 A074137 A074138 * A074140 A074141 A074142


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



