login
A127106
Numbers n such that n^2 divides 6^n-1.
42
1, 5, 1555, 9673655, 187159211791705, 776119592182705
OFFSET
1,2
COMMENTS
Subsequence of A014946.
MATHEMATICA
Select[Range[20000], IntegerQ[(PowerMod[6, #, #^2 ]-1)/#^2 ]&]
KEYWORD
hard,more,nonn
AUTHOR
Alexander Adamchuk, Jan 05 2007
EXTENSIONS
Two more terms from Max Alekseyev, May 05 2010
STATUS
approved