OFFSET
1,2
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..5000
MATHEMATICA
f[l_] := Append[l, l[[ -1]] + Count[MemberQ[l, # ] & /@ Union@DivisorSigma[0, l], True]]; Nest[f, {1}, 58]
CROSSREFS
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Aug 26 2007
STATUS
approved