This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A182095 #33 Jun 11 2024 04:35:20
%S A182095 0,0,1,5,10,24,50,104,212,436,886,1792,3631,7319,14771,29737,59826,
%T A182095 120322,241753,485652,974989,1956815,3926087,7874899,15791397,
%U A182095 31660311,63463119,127190437,254873548,510663633,1023044286,2049300991,4104631710,8220611286
%N A182095 Number of composite numbers between 2^n and 2^(n+1).
%C A182095 Note that here, the endpoints of the interval are not counted. - _Michel Marcus_, Sep 05 2013
%H A182095 Amiram Eldar, <a href="/A182095/b182095.txt">Table of n, a(n) for n = 0..91</a> (terms 0..45 from G. C. Greubel)
%F A182095 a(n) = 2^n - 1 - A036378(n) for n >= 1. - _T. D. Noe_, Apr 11 2012
%F A182095 a(n) = A075084(2^n) - 2, for n>0. - _Michel Marcus_, Sep 05 2013
%e A182095 Between 2^3 and 2^4 there are 5 composite integers: 9, 10, 12, 14, and 15.
%t A182095 Join[{0}, Table[2^n - (PrimePi[2^(n + 1)] - PrimePi[2^n]) - 1, {n, 33}]] (* _T. D. Noe_, Apr 11 2012 *)
%o A182095 (Magma) [0] cat [2^n-(#PrimesUpTo(2^(n+1))-#PrimesUpTo(2^n))-1: n in [1..28]]; // _Vincenzo Librandi_, Aug 21 2017
%Y A182095 Cf. A036378 (number of primes between 2^n and 2^(n+1)), A075084.
%K A182095 nonn
%O A182095 0,4
%A A182095 _Antoine Gold_, Apr 11 2012