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 A067421 #12 Jun 29 2023 10:43:39 %S A067421 1,8,144,2592,46656,839808,15116544,272097792,4897760256,88159684608, %T A067421 1586874322944,28563737812992,514147280633856,9254651051409408, %U A067421 166583718925369344,2998506940656648192 %N A067421 Sixth column of triangle A067417. %H A067421 Vincenzo Librandi, <a href="/A067421/b067421.txt">Table of n, a(n) for n = 0..800</a> %H A067421 <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (18). %F A067421 a(n) = A067417(n+5, 5). %F A067421 a(n) = 8*(3*6)^(n-1), n >= 1, a(0)=1. %F A067421 G.f.: (1-10*x)/(1-18*x). %o A067421 (Magma) [Ceiling(8*(3*6)^(n-1)): n in [0..20]]; // _Vincenzo Librandi_, Oct 02 2011 %Y A067421 Cf. A067420 (fifth column), A067422 (seventh column), A001027 (powers of 18). %K A067421 nonn,easy %O A067421 0,2 %A A067421 _Wolfdieter Lang_, Jan 25 2002