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Decimal expansion of log_2(5).
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%I #40 Dec 01 2022 08:57:31

%S 2,3,2,1,9,2,8,0,9,4,8,8,7,3,6,2,3,4,7,8,7,0,3,1,9,4,2,9,4,8,9,3,9,0,

%T 1,7,5,8,6,4,8,3,1,3,9,3,0,2,4,5,8,0,6,1,2,0,5,4,7,5,6,3,9,5,8,1,5,9,

%U 3,4,7,7,6,6,0,8,6,2,5,2,1,5,8,5,0,1,3,9,7,4,3,3,5,9,3,7,0,1,5

%N Decimal expansion of log_2(5).

%C Equals the Hausdorff dimension of the Sierpinski fractal square-based pyramid, when each square-based pyramid is replaced by 5 half-size such square-based pyramids (see IREM link). - _Bernard Schott_, Nov 30 2022

%H Vincenzo Librandi, <a href="/A020858/b020858.txt">Table of n, a(n) for n = 1..1000</a>

%H IREM Paris-Nord, <a href="http://www-irem.univ-paris13.fr/site_spip/spip.php?article369">La pyramide de Sierpinski</a> (in French).

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/List_of_fractals_by_Hausdorff_dimension">List of fractals by Hausdorff dimension</a> (see Fractal pyramid).

%H <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a>

%e 2.3219280...

%t RealDigits[Log[2,5],10,120][[1]] (* _Harvey P. Dale_, Oct 20 2011 *)

%o (PARI) log(5)/log(2) \\ _Charles R Greathouse IV_, Aug 06 2020

%Y Cf. decimal expansion of log_2(m): A020857 (m=3), this sequence, A020859 (m=6), A020860 (m=7), A020861 (m=9), A020862 (m=10), A020863 (m=11), A020864 (m=12), A152590 (m=13), A154462 (m=14), A154540 (m=15), A154847 (m=17), A154905 (m=18), A154995 (m=19), A155172 (m=20), A155536 (m=21), A155693 (m=22), A155793 (m=23), A155921 (m=24).

%Y Sierpinski pyramid: A000351 (number of pyramids), A279511 (number of vertices).

%K nonn,cons

%O 1,1

%A _N. J. A. Sloane_

%E Definition improved by _J. Lowell_, May 03 2014