OFFSET
1,1
COMMENTS
The terms a(5) etc. have at least 63 digits (if they exist), so the pattern of terms does not continue as in A001039. [From R. J. Mathar, Feb 27 2010]
MATHEMATICA
f1[n_]:=Module[{s=0}, Do[s+=n^a, {a, 0, n-1}]; s]; f2[n_]:=Last/@FactorInteger[n]=={1, 1}||Last/@FactorInteger[n]=={2}; Select[Table[f1[n], {n, 50}], f2[ # ]&]
CROSSREFS
KEYWORD
nonn
AUTHOR
Vladimir Joseph Stephan Orlovsky, Feb 19 2010
STATUS
approved