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A173339
Positive integers n for which the number of divisors of n^n is a square.
2
1, 3, 4, 6, 8, 10, 14, 15, 21, 22, 26, 33, 34, 35, 36, 38, 39, 46, 51, 55, 57, 58, 60, 62, 65, 69, 74, 77, 82, 84, 85, 86, 87, 91, 93, 94, 95, 100, 106, 111, 115, 118, 119, 120, 122, 123, 129, 133, 134, 141, 142, 143, 145, 146
OFFSET
1,2
PROG
(PARI) isok(n) = issquare(numdiv(n^n)); \\ Michel Marcus, Jul 09 2014
CROSSREFS
Sequence in context: A256698 A024182 A301752 * A064269 A260485 A373846
KEYWORD
nonn
AUTHOR
John W. Layman, Feb 16 2010
STATUS
approved