A068400 Numbers k such that sigma(k) = phi(k*bigomega(k)).

248, 357, 1045, 3596, 3956, 4064, 5396, 8636, 20026, 20320, 23374, 24871, 25714, 29029, 33915, 35074, 39585, 41656, 50065, 55154, 56134, 56536, 58435, 61344, 64285, 74613, 79000, 87087, 87685, 137885, 140335, 142240

Offset

1,1

Comments

Comment from Giovanni Resta, Nov 15 2006: For all the numbers listed, gcd(n!-1,2^n+1) = 2n+1. Is this always true? Reply from Max Alekseyev, Nov 16 2006: This is plausible and true for n up to 45000.

Links

Table of n, a(n) for n=1..32.

Crossrefs

Sequence in context: A187398 A065146 A064977 * A240967 A230856 A109478

Adjacent sequences: A068397 A068398 A068399 * A068401 A068402 A068403

Keyword

easy,nonn

Author

Benoit Cloitre, Mar 02 2002

Status

approved