OFFSET
1,1
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
MATHEMATICA
s[n_] := DivisorSum[n, # &, #^2 < n && CoprimeQ[#, n/#] &]; Select[Range[3000], s[#] == s[# + 1] &]
CROSSREFS
KEYWORD
nonn
AUTHOR
Amiram Eldar, Apr 12 2020
STATUS
approved