OFFSET
1,1
COMMENTS
Corresponding values of sigma(p) of primes p from A158913.
FORMULA
a(n) = A158913(n) + 1.
MATHEMATICA
Union@ Select[ DivisorSigma[1, Select[ Range@ 100, !PrimeQ@# &]], PrimeQ[# - 1] &] (* Robert G. Wilson v, Feb 09 2012 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Feb 07 2012
STATUS
approved