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A325913 Integers m such that there are exactly two powers of 2 between 3^m and 3^(m+1).

%I A325913 #45 Dec 22 2021 10:18:00
%S A325913 1,3,5,6,8,10,11,13,15,17,18,20,22,23,25,27,29,30,32,34,35,37,39,41,
%T A325913 42,44,46,47,49,51,52,54,56,58,59,61,63,64,66,68,70,71,73,75,76,78,80,
%U A325913 82,83,85,87,88,90,92,94,95,97,99,100
%N A325913 Integers m such that there are exactly two powers of 2 between 3^m and 3^(m+1).
%C A325913 Or m such that A022921(m) = 2.
%C A325913 Also largest m such that 2^(m+n) > 3^m. - _Bob Selcoe_, Dec 19 2021
%H A325913 Benjamin Lombardo, <a href="/A325913/b325913.txt">Table of n, a(n) for n = 1..1000</a>
%F A325913 a(n) = floor(n/(log_2(3)-1)).
%F A325913 a(n) = A054414(n) - n - 1.
%e A325913 For m=3, there are exactly two powers of 2 between 3^3 = 27 and 3^(3+1) = 81: 32 and 64, since 27 < 32 < 64 < 81. Therefore, m=3 is an element of the sequence (at n=2).
%o A325913 (Python)
%o A325913 import math
%o A325913 def a(n):
%o A325913     return math.floor(n/(math.log2(3)-1))
%o A325913 for n in range(1, 101):
%o A325913     print("a(" + str(n) + ") = " + str(a(n)))
%Y A325913 Cf. A022921, A054414.
%K A325913 nonn
%O A325913 1,2
%A A325913 _Benjamin Lombardo_, Sep 08 2019