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%I #14 Oct 24 2016 01:56:37
%S 1,2,3,5,7,9,11,13,15,17,19,21,23,25,29,31,33,35,37,39,41,43,47,49,51,
%T 53,55,57,59,61,65,67,69,71,73,75,77,79,83,85,87,89,91,93,95,97,101,
%U 103,105,107,109,111,113,115,119,121,123,127,129,131,133,137,139,141,143,145,147,149,151,155,157,159,161,163,165,167,169
%N Numbers n, that apart from 2 are all odd and for which n/(largest prime dividing n) is squarefree.
%C In other words, after 1 and 2, such odd numbers that only the largest prime factor in their prime factorization may have exponent 1 or 2, while all lesser prime factors occur at most once.
%H Antti Karttunen, <a href="/A277334/b277334.txt">Table of n, a(n) for n = 1..10000</a>
%p with(numtheory): A277334_list := n -> seq(`if`(i=2 or (i::odd and issqrfree(i/ max(factorset(i)))),i,NULL),i=1..n): A277334_list(169); # _Peter Luschny_, Oct 23 2016
%o (Scheme, with _Antti Karttunen_'s IntSeq-library)
%o (define A277334 (MATCHING-POS 1 1 (lambda (n) (and (or (= 2 n) (not (even? n))) (not (zero? (A008683 (A052126 n))))))))
%Y Disjoint union of A056911 and A129598(A056911(n)).
%Y Cf. A005117, A008683, A052126.
%Y Cf. A277332 (permutation of this sequence).
%Y Differs from A091377 for the first time at n=36, where a(36)=75, while A091377(36)=77.
%K nonn
%O 1,2
%A _Antti Karttunen_, Oct 12 2016
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