|
%I #11 May 19 2020 09:12:53
%S 1,4,9,16,25,36,64,81,100,121,144,225,256,289,324,400,484,529,576,625,
%T 729,841,900,1024,1089,1156,1296,1600,1681,1936,2025,2116,2209,2304,
%U 2401,2500,2601,2809,2916,3025,3364,3481,3600,4096,4356,4624,4761,5041
%N The smallest k>1 such that k divides sigma(k*n) is equal to 6.
%C The smallest k>1 such that k divides sigma(k*n) is always 2, 3 or 6. Sequence generates squares but not all the squares (49, 169, 196, 361, 441, 676, 784, ... are the first squares not in the sequence).
%C This is not the sequence of solutions to sigma(n) == 1 (mod 6), because 2401 is in this sequence but sigma(2401) == 5 (mod 6). See A074384 for more examples. - _R. J. Mathar_, May 19 2020
%F {n: A049605(n) = 6}. - _R. J. Mathar_, May 19 2020
%K easy,nonn
%O 1,2
%A _Benoit Cloitre_, Jul 26 2002
|
