OFFSET
1,12
LINKS
MATHEMATICA
f[n_] := DivisorSigma[1, n] - 2 n; Array[DivisorSum[#, f, f@ # >= 0 &] &, 105] (* Michael De Vlieger, Sep 04 2018 *)
PROG
(PARI) A318679(n) = sumdiv(n, d, d=sigma(d)-(2*d); (d>0)*d);
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Sep 04 2018
STATUS
approved