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 A153131 #8 Aug 14 2023 11:04:32 %S A153131 4,5,5,3,4,0,4,9,7,3,9,3,9,0,5,9,9,5,9,6,4,1,5,1,9,4,4,2,0,1,7,8,1,9, %T A153131 9,1,2,8,2,1,3,1,1,8,2,4,8,2,6,4,6,5,9,2,3,3,4,1,4,9,9,1,3,4,3,1,2,1, %U A153131 7,3,6,8,5,1,3,7,0,9,5,3,5,1,6,5,7,6,8,9,6,3,0,5,3,4,6,8,1,7,7 %N A153131 Decimal expansion of log_21 (4). %H A153131 Vincenzo Librandi, <a href="/A153131/b153131.txt">Table of n, a(n) for n = 0..1000</a> %H A153131 <a href="/index/Tra#transcendental">Index entries for transcendental numbers</a> %e A153131 .45534049739390599596415194420178199128213118248264659233414... %t A153131 RealDigits[Log[21, 4], 10, 100][[1]] (* _Vincenzo Librandi_, Sep 06 2013 *) %Y A153131 Cf. decimal expansion of log_21(m): A152825 (m=2), A153097 (m=3), this sequence, A153455 (m=5), A153611 (m=6), A153632 (m=7), A153895 (m=8), A154020 (m=9), A154171 (m=10), A154192 (m=11), A154213 (m=12), A154434 (m=13), A154499 (m=14), A154707 (m=15), A154839 (m=16), A154901 (m=17), A154977 (m=18), A155129 (m=19), A155532 (m=20), A155790 (m=22), A155909 (m=23), A156028 (m=24). %K A153131 nonn,cons %O A153131 0,1 %A A153131 _N. J. A. Sloane_, Oct 30 2009