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%I #9 Feb 14 2021 13:06:38
%S 4,45,175,1573,5491,26071,72283,212341,367993,1050703,1247941,2608891,
%T 3352351,5799421,7040833,7722991,11800141,13766161,19609831,22345963,
%U 30273673,42022741,73911181,80434513,98397223,141963643,184867531,215639401,235646491,264196483
%N Numbers k such that (sigma(k)-k) - Sum_{p|k} p^2 = -1.
%F a(1)=4; a(n+1) = A001359(n)^2*(A001359(n)+2) where A001359 lists number that are the lesser of twin primes.
%o (PARI) for(n=1,1000000,if(sumdiv(n,d,d)-n+1-sumdiv(n,d,isprime(d)*d^2)==0,print1(n,",")))
%K easy,nonn
%O 1,1
%A _Benoit Cloitre_, May 07 2002
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