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%I #39 Sep 26 2018 10:09:01
%S 3,34,5,15,17,55,79,5,53,23,337,13,601,79,241,41,18433,31,40961,89,
%T 3313,1153
%N Least number k such that k^n and k^n-1 contain the same number of prime factors (counted with multiplicity) or 0 if no such k exists.
%C a(23) > 3250.
%C a(24) = 79. - _Jacques Tramu_, Sep 16 2018
%C 100000 < a(23) <= 286721. - _Jon E. Schoenfield_, Sep 25 2018
%e 2^1 (2) and 2^1-1 (1) do not have the same number of prime factors. 3^1 (3) and 3^1-1 (2) have the same number of prime factors. Thus a(1) = 3.
%o (PARI) a(n)=for(k=2,oo,if(bigomega(k^n)==bigomega(k^n-1),return(k)));
%Y Cf. A001222 (bigomega), A242786.
%K nonn,more,hard
%O 1,1
%A _Derek Orr_, May 23 2014
%E a(17) and a(19) corrected by _Jacques Tramu_, Sep 16 2018
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