0,2

sigma_12(n) is the sum of the 12th powers of the divisors of n.

sigma[24j+12,x]/phi[x] is an integer for j in the range 0,..,500 for x=1,2,3,6,249,498,118578 and supposed to hold for possible larger terms of A015770 and all j. Compare with comments to A015759, A091285, A015762. - Labos E. (labos(AT)ana.sote.hu), May 27 2004

Adjacent sequences: A015767 A015768 A015769 this_sequence A015771 A015772 A015773

Sequence in context: A018734 A018755 A018769 this_sequence A015762 A093038 A094469

nonn

Robert G. Wilson v (rgwv(AT)rgwv.com)