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A102862 Numbers of prime factors of the sum of the first n primes.

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%I A102862 #13 Dec 22 2022 18:38:57
%S A102862 1,1,2,1,3,1,2,2,4,2,6,1,3,1,4,2,5,2,4,3,4,2,3,3,4,4,5,2,5,4,5,2,4,2,
%T A102862 3,2,5,2,3,5,3,3,3,2,4,2,3,2,5,3,4,6,4,2,2,3,4,2,2,1,3,3,3,1,2,2,3,3,
%U A102862 3,3,5,2,3,4,2,3,4,3,6,4,3,2,6,4,5,3,5,4,4,3,5,2,2,2,6,1,4,3,5,1,5,1,7,2,5
%N A102862 Numbers of prime factors of the sum of the first n primes.
%H A102862 Amiram Eldar, <a href="/A102862/b102862.txt">Table of n, a(n) for n = 1..10000</a>
%F A102862 a(n) = A001222(A007504(n)). - _Amiram Eldar_, Mar 09 2020
%e A102862 a(3) = 2 because 2+3+5 = 10 = 2*5.
%e A102862 a(5) = 3 because 2+3+5+7+11 = 28 = 2*2*7.
%t A102862 PrimeOmega @ Accumulate @ Select[Range[230], PrimeQ] (* _Amiram Eldar_, Mar 09 2020 *)
%t A102862 PrimeOmega[Accumulate[Prime[Range[110]]]] (* _Harvey P. Dale_, Dec 22 2022 *)
%o A102862 (PARI) for(n=1,105,print1(bigomega(sum(k=1,n,prime(k))),",")) \\ _Rick L. Shepherd_, May 17 2005
%Y A102862 Cf. A001222, A007504.
%K A102862 nonn
%O A102862 1,3
%A A102862 _Giovanni Teofilatto_, Mar 01 2005
%E A102862 More terms from _Rick L. Shepherd_, May 17 2005