OFFSET
1,2
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..16384
MATHEMATICA
Table[GCD[n, DivisorSigma[1, n+1]], {n, 110}] (* Harvey P. Dale, May 25 2015 *)
PROG
(PARI) j=[]; for(n=1, 200, j=concat(j, gcd(n, sigma(n+1)))); j
(PARI) a(n) = gcd(n, sigma(n+1)); \\ Michel Marcus, Dec 16 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Jason Earls, Jul 15 2001
STATUS
approved