OFFSET
1,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..999 (offset adapted by Michel Marcus)
FORMULA
MAPLE
for i from 1 to 500 do if isprime(i) then print(sigma(i+1)); fi; od;
MATHEMATICA
lst={}; Do[AppendTo[lst, DivisorSigma[1, Prime[n]+1]], {n, 6!}]; lst (* Vladimir Joseph Stephan Orlovsky, Sep 20 2008 *)
PROG
(PARI) a(n) = sigma(prime(n)+1); \\ Michel Marcus, May 11 2016
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
EXTENSIONS
Offset 1 from Michel Marcus, Apr 19 2020
STATUS
approved