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 A198852 #33 May 29 2024 19:58:24 %S A198852 3,31,255,2047,16383,131071,1048575,8388607,67108863,536870911, %T A198852 4294967295,34359738367,274877906943,2199023255551,17592186044415, %U A198852 140737488355327,1125899906842623,9007199254740991,72057594037927935,576460752303423487,4611686018427387903 %N A198852 a(n) = 4*8^n - 1. %C A198852 In base 8, the numbers of this sequence are written 37, 377, 3777, 37777, ... and satisfy the A052148 condition. - _Michel Marcus_, Aug 23 2013 %H A198852 Vincenzo Librandi, <a href="/A198852/b198852.txt">Table of n, a(n) for n = 0..1000</a> %H A198852 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (9,-8). %F A198852 a(n) = 8*a(n-1) + 7. %F A198852 a(n) = 9*a(n-1) - 8*a(n-2) for n > 1. %F A198852 G.f.: ( 3+4*x ) / ( (8*x-1)*(x-1) ). - _R. J. Mathar_, Oct 31 2011 %F A198852 a(n) = A013731(n) - 1. - _Michel Marcus_, Aug 23 2013 %F A198852 E.g.f.: exp(x)*(4*exp(7*x) - 1). - _Stefano Spezia_, May 29 2024 %o A198852 (Magma) [4*8^n-1: n in [0..30]]; %Y A198852 Cf. A013731, A052148. %K A198852 nonn,easy %O A198852 0,1 %A A198852 _Vincenzo Librandi_, Oct 31 2011