A295307 Numbers k such that k > phi(sigma(k)), where phi = A000010 and sigma = A000203.

3, 5, 6, 7, 10, 11, 13, 14, 15, 17, 19, 20, 21, 22, 23, 24, 26, 27, 28, 29, 30, 31, 33, 34, 35, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 49, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 65, 66, 67, 68, 69, 70, 71, 73, 74, 75, 76, 77, 78, 79, 80, 82, 83, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 99, 101

Offset: 1

Author

Antti Karttunen, Nov 21 2017

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A000010, A000203, A062401, A295309 (characteristic function).

Positions of positive terms in A295301 & A295303.

Differs from A073803 for the first time at n=39, as here a(39) = 52, the value which does not occur in A073803.

Programs

Mathematica

Select[Range@ 101, # > EulerPhi@ DivisorSigma[1, #] &] (* Michael De Vlieger, Nov 22 2017 *)

Formula

Numbers k such that A295301(k) > 0.