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 A320862 #17 Sep 08 2022 08:46:23 %S A320862 64,65536,67108864,68719476736,604462909807314587353088, %T A320862 618970019642690137449562112,633825300114114700748351602688, %U A320862 649037107316853453566312041152512,664613997892457936451903530140172288,680564733841876926926749214863536422912 %N A320862 Powers of 2 with initial digit 6. %H A320862 Muniru A Asiru, <a href="/A320862/b320862.txt">Table of n, a(n) for n = 1..220</a> %H A320862 <a href="/index/Di#divseq">Index to divisibility sequences</a> %p A320862 select(x->"6"=""||x[1],[2^n$n=0..180])[]; %t A320862 Select[2^Range[160], First[IntegerDigits[#]] == 6 &] (* _G. C. Greubel_, Oct 27 2018 *) %o A320862 (GAP) Filtered(List([0..180],n->2^n),i->ListOfDigits(i)[1]=6); %o A320862 (PARI) select(x->(digits(x)[1]==6), vector(200, n, 2^n)) \\ _Michel Marcus_, Oct 26 2018 %o A320862 (Magma) [2^n: n in [1..160] | Intseq(2^n)[#Intseq(2^n)] eq 6]; // _G. C. Greubel_, Oct 27 2018 %Y A320862 Cf. A000079 (powers of 2), A008952 (leading digit of 2^n), A217399 (numbers starting with 6). %Y A320862 Powers of 2 with initial digit k, (k = 1..6): A067488, A067480, A320859, A320860, A320861, this sequence. %K A320862 base,nonn %O A320862 1,1 %A A320862 _Muniru A Asiru_, Oct 23 2018