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%I #19 Dec 25 2020 11:10:15
%S 5,23,25,31,41,43,47,53,67,101,109,113,127,137,141,149,155,187,191,
%T 195,203,209,253,275,317,322,329,367,389,409,415,503,537,565,613,623,
%U 637,643
%N Numbers m such that 3^m-1 and 3^m+1 have the same number k of prime factors counted with multiplicity.
%C Corresponding values of k: {3, 3, 5, 4, 4, 3, 4, 4, 4, 6, 9}.
%e 3^5 - 1 = 242 = 2*11*11, 3^5 + 1 = 244 = 2*2*61 (both are 3-almost primes (A110187)).
%o (PARI) isok(m) = bigomega(3^m-1) == bigomega(3^m+1); \\ _Michel Marcus_, Dec 14 2020
%Y Cf. A001222, A057941, A057958.
%K nonn,more
%O 1,1
%A _Zak Seidov_, Dec 14 2020
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