cp's OEIS Frontend

A082876 Number of prime divisors (counted with multiplicity) of numbers of form a^n + b^n + c^n + ..., where a*b*c* ... is the prime factorization of n.

%I A082876 #10 Apr 01 2020 22:18:02
%S A082876 0,2,3,5,5,2,7,9,10,3,11,1,13,5,7,18,17,4,19,3,7,7,23,3,26,6,28,3,29,
%T A082876 4,31,33,8,5,11,6,37,7,9,3,41,5,43,5,4,7,47,5,50,8,14,7,53,5,11,4,8,9,
%U A082876 59,4,61,9,5,66,11,4,67,7,11,11,71,7,73,9,4
%N A082876 Number of prime divisors (counted with multiplicity) of numbers of form a^n + b^n + c^n + ..., where a*b*c* ... is the prime factorization of n.
%C A082876 A082872(2) and A082872(6) are semiprimes. Where is the next?
%o A082876 (PARI) a(n) = if(n<2, 0, bigomega(sum(i=1, matsize(f=factor(n))[1], f[i, 1]^n*f[i, 2]))); \\ _Jinyuan Wang_, Apr 01 2020
%Y A082876 Cf. A001222, A082813, A082814, A082872.
%K A082876 nonn,more
%O A082876 1,2
%A A082876 _Jason Earls_, May 25 2003
%E A082876 a(74)-a(75) from _Jinyuan Wang_, Apr 01 2020