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%I #11 Mar 09 2020 22:10:19
%S 46,58,74,94,106,118,122,134,142,158,166,194,202,206,214,262,267,274,
%T 278,298,309,314,326,334,339,346,358,362
%N Squarefree semiprimes which never occur in A245486.
%C Also squarefree semiprimes which never occur in A332951.
%C This sequence is infinite. It appears that all terms can be divisible by 2 or 3.
%C If A014664(i) = A014664(j) for some 1 < i < j, then 2*prime(i) is a term. See A245486 for more information.
%H Romanian Master in Mathematics Contest, Bucharest, 2020, <a href="https://artofproblemsolving.com/community/c6h2019180">Problem 6</a>
%e a(2) = 58 because when 2^m - 1 or 2^m + 1 is divisible by 29, it's also divisible by 113. Therefore, there's no integer k such that A245486(k) = A006530(k) * A006530(k+1) = 58.
%Y Cf. A000040, A006530, A006881, A014664, A245486, A332951.
%K nonn,more
%O 1,1
%A _Jinyuan Wang_, Mar 04 2020
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