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%I #23 Sep 08 2022 08:45:04
%S 1,5,6,7,11,13,17,19,23,25,29,30,31,35,36,37,41,42,43,47,49,53,55,59,
%T 61,65,66,67,71,73,77,78,79,83,85,89,91,95,97,101,102,103,107,109,113,
%U 114,115,119,121,125,127,131,133,137,138,139,143,145,149,150,151,155
%N Numbers of the form m * 6^k for k >= 0 and m > 0 with gcd(m, 6) = 1.
%C These are the fixed points of A064614, a permutation of natural numbers: A064614(a(n)) = a(n), for all n.
%C Numbers n such that exponent of highest power of 2 dividing n is equal to exponent of highest power of 3 dividing n. - _Juri-Stepan Gerasimov_, Sep 01 2016
%C All primes >3 are terms. - _Zak Seidov_, Sep 02 2016
%H Amiram Eldar, <a href="/A064615/b064615.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = 5n/2 + O(log n). - _Charles R Greathouse IV_, Sep 02 2016
%p q:= n-> is(padic[ordp](n, 2)=padic[ordp](n, 3)):
%p select(q,[$1..200])[]; # _Alois P. Heinz_, Oct 28 2021
%t okQ[n_] := IntegerExponent[n, 2] == IntegerExponent[n, 3];
%t Select[Range[200], okQ] (* _Jean-François Alcover_, Oct 28 2021 *)
%o (PARI) is(n)=valuation(n,2)==valuation(n,3) \\ _Charles R Greathouse IV_, Sep 02 2016
%o (Magma) [n: n in [1..200] |Valuation(n, 2) eq Valuation(n, 3)]; // _Vincenzo Librandi_, Sep 02 2016
%Y Cf. A064614.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Sep 25 2001
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