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%I #6 Jul 19 2017 21:32:12
%S 1,3,5,9,11,15,17,23,25,27,29,33,41,45,47,51,53,55,59,69,71,75,81,83,
%T 85,87,89,99,101,107,113,115,121,123,125,131,135,137,141,145,149,153,
%U 159,165,167,173,177,179,187,191,197,205,207,213,225,227,233,235,239
%N Natural numbers whose prime factors are all congruent to 3 or 5 mod 6 (i.e., are in the sequence A045410).
%C 1 is included, as it has no prime factors at all, thus no prime factors outside of A045410.
%H A. Karttunen, <a href="/A166104/b166104.txt">Table of n, a(n) for n = 1..1001</a>
%o (MIT Scheme with macro MATCHING-POS by AK:)
%o (define A166104 (MATCHING-POS 1 1 (lambda (n) (for-all? (factor n) (lambda (p) (or (= 1 p) (= 3 p) (= 5 (modulo p 6))))))))
%Y See the conjecture at A166103. Cf. A045410.
%K nonn
%O 1,2
%A _Antti Karttunen_, Oct 13 2009