OFFSET
1,1
LINKS
Robert Israel, Table of n, a(n) for n = 1..1100
MAPLE
spf:= proc(n) local t; add(t[1]*t[2], t=ifactors(n)[2]) end proc:
select(p -> spf(p+1)=spf(p-1)-1, [seq(ithprime(i), i=1..10^5)]);
CROSSREFS
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, Mar 22 2021
STATUS
approved