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%I #10 Oct 30 2022 07:06:18
%S 18,88,4030,5830,518656,13174976,134094848,2146926592
%N Numbers k such that sigma(k) = 2k + Omega(k), where Omega(n) is the number of prime divisors of n (with repetition).
%C From Donovan Johnson_, Dec 19 2008: (Start)
%C a(9) <= 2251798907715584.
%C a(10) <= 633825300114085990300727115776.
%C a(11) <= 2596148429267411760623818083663872. (End)
%C a(9) > 10^13. - _Giovanni Resta_, Jul 13 2015
%F Numbers k such that A000203(k) = 2k + A001222(k). - _Wesley Ivan Hurt_, Oct 30 2022
%o (PARI) for(n=1,10^8, if(sigma(n)==2*n+bigomega(n),print(n)))
%Y Cf. A000203 (sigma), A001222 (Omega).
%K more,nonn
%O 1,1
%A _Jason Earls_, Aug 16 2001
%E a(7)-a(8) from _Donovan Johnson_, Dec 19 2008
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