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A054011 n is not divisible by the number of its proper divisors. 2
8, 9, 10, 12, 14, 18, 22, 24, 25, 26, 28, 30, 32, 34, 35, 36, 38, 40, 44, 46, 48, 49, 52, 54, 55, 58, 60, 62, 63, 64, 65, 66, 68, 72, 74, 76, 77, 78, 80, 81, 82, 84, 85, 86, 88, 90, 91, 92, 94, 95, 96, 98, 99, 100, 102, 104, 106, 108, 110, 112, 114, 115, 116, 117, 118, 119 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

MAPLE

with(numtheory): [seq(`if`(i mod (tau(i)-1) <> 0, i, print( )), i=2..190)];

MATHEMATICA

Select[Range[2, 120], ! Divisible[#, DivisorSigma[0, #] - 1] &] (* Amiram Eldar, Aug 28 2019 *)

CROSSREFS

Cf. A000005, A032741, A054009, A054012.

Sequence in context: A031009 A120184 A068019 * A280946 A209724 A114842

Adjacent sequences:  A054008 A054009 A054010 * A054012 A054013 A054014

KEYWORD

nonn

AUTHOR

Asher Auel (asher.auel(AT)reed.edu), Jan 17 2000

STATUS

approved

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Last modified October 20 02:18 EDT 2019. Contains 328244 sequences. (Running on oeis4.)