OFFSET
1,3
COMMENTS
Right border of A299762. - Omar E. Pol, Mar 14 2018
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
EXAMPLE
11 is the largest k such that sigma(k) = 12, so a(12) = 11.
MATHEMATICA
a[n_] := Module[{k = n}, While[k > 0 && DivisorSigma[1, k] != n, k--]; k]; Array[a, 90] (* Amiram Eldar, Jan 05 2020 *)
PROG
CROSSREFS
KEYWORD
nonn
AUTHOR
Jud McCranie, Oct 10 2000
STATUS
approved