OFFSET
1,6
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
EXAMPLE
a(6) = 2 since there are 2 solutions to esigma(x) = 6 (esigma is A051377): 4 and 6.
MATHEMATICA
f[p_, e_] := DivisorSum[e, p^# &]; esigma[1] = 1; esigma[n_] := Times @@ f @@@ FactorInteger[n]; m = 100; v = Table[0, {m}]; Do[e = esigma[k]; If[e <= m, v[[e]]++], {k, 1, m}]; v
CROSSREFS
KEYWORD
nonn
AUTHOR
Amiram Eldar, Feb 05 2020
STATUS
approved