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A255542 a(n) = number of prime factors of (3^n + 10) counted with multiplicity.

%I A255542 #18 Oct 09 2024 07:31:58
%S A255542 1,1,1,1,2,2,1,3,1,2,4,3,2,3,2,3,5,3,1,3,3,3,4,2,3,4,2,6,4,3,3,4,3,2,
%T A255542 5,4,1,4,5,5,5,2,4,3,3,5,5,2,2,5,4,3,4,3,3,6,4,4,5,5,7,3,3,4,5,5,2,6,
%U A255542 3,5,5,4,4,5,3,7,6,4,4,3,2,4,5,4,2,4,3,2,4,4,4,5,4,6,7,4,3,5,1,4
%N A255542 a(n) = number of prime factors of (3^n + 10) counted with multiplicity.
%H A255542 Amiram Eldar, <a href="/A255542/b255542.txt">Table of n, a(n) for n = 0..257</a> (terms 0..151 from Zak Seidov)
%F A255542 a(n) = A001222(3^n+10).
%e A255542 a(0) = 1 because 3^0+10 = 11 is prime.
%e A255542 a(4) = 2 because 3^4+10 = 91 = 7*13 is semiprime.
%e A255542 a(7) = 3 because 3^7+10 = 2197 = 13*13*13 is 3-almost prime.
%e A255542 a(10) = 4 because 3^7+10 = 59059 = 7*11*13*59 is 4-almost prime.
%e A255542 a(16) = 5 because 3^16+10 = 43046731 = 7*13*23*131*157 is 5-almost prime.
%t A255542 a[n_]:= PrimeOmega[3^n+10];
%o A255542 (PARI) a(n) = bigomega(3^n+10);
%Y A255542 Cf. A001222, A102907, A217137.
%K A255542 nonn
%O A255542 0,5
%A A255542 _Zak Seidov_, Feb 25 2015