OFFSET
1,6
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..16384
Antti Karttunen, Data supplement: n, a(n) computed for n = 1..65537
MATHEMATICA
Array[DivisorSum[#, # &, SquareFreeQ] - # &, 86] (* Michael De Vlieger, Apr 21 2019 *)
PROG
CROSSREFS
KEYWORD
sign
AUTHOR
Antti Karttunen, Apr 21 2019
STATUS
approved