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A046678
Number of divisors of n and sum of divisors of n are relatively prime.
9
1, 2, 4, 8, 9, 16, 25, 36, 64, 81, 100, 121, 128, 144, 162, 225, 256, 289, 324, 400, 484, 512, 529, 576, 625, 729, 841, 900, 1024, 1089, 1156, 1250, 1296, 1458, 1600, 1681, 1936, 2025, 2116, 2209, 2304, 2401, 2500, 2601, 2809, 3025, 3364, 3481
OFFSET
1,2
COMMENTS
It can be shown that this is a subsequence of A028982.
LINKS
MATHEMATICA
Select[Range[3490], CoprimeQ[DivisorSigma[1, #], DivisorSigma[0, #]] &] (* Jayanta Basu, Jun 27 2013 *)
PROG
(PARI) isok(n) = gcd(sigma(n), numdiv(n)) == 1; \\ Michel Marcus, Sep 24 2019
KEYWORD
nonn
AUTHOR
STATUS
approved