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A338519
Integers that can be expressed as a product d*tau(d), where tau is the number of divisors function, in a single way.
3
1, 4, 6, 10, 12, 14, 22, 24, 26, 27, 32, 34, 38, 40, 46, 56, 58, 60, 62, 72, 74, 75, 80, 82, 84, 86, 88, 94, 104, 106, 118, 120, 122, 132, 134, 136, 140, 142, 146, 147, 152, 156, 158, 166, 168, 178, 184, 194, 202, 204, 206, 214, 218, 220, 226, 228, 232, 240, 248, 254
OFFSET
1,2
COMMENTS
Integers m such that A327166(m) = 1.
LINKS
PROG
(PARI) f(n) = sumdiv(n, d, d*numdiv(d) == n); \\ A327166
isok(n) = f(n)==1;
CROSSREFS
Subsequences: A100484 (2*p), A079705 (3*p^2) that gives odd terms.
Cf. A338520 (similar for sum of divisors).
Sequence in context: A102070 A026402 A036438 * A066190 A058012 A026411
KEYWORD
nonn
AUTHOR
Michel Marcus, Nov 01 2020
STATUS
approved