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 A255813 #15 Oct 12 2022 09:34:20
%S A255813 1,3,10,34,115,388,1309,4417,14905,50296,169720,572707,1932556,
%T A255813 6521263,22005505,74255899,250570870,845532298,2853184279,9627852832,
%U A255813 32488455385,109629815881,369937455865,1248325741972,4212380047936
%N A255813 Numbers of words on {0,1,2,3} having no isolated zeros.
%H A255813 G. C. Greubel, <a href="/A255813/b255813.txt">Table of n, a(n) for n = 0..1000</a>
%H A255813 D. Birmajer, J. B. Gil, and M. D. Weiner, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL19/Gil/gil6.html">On the Enumeration of Restricted Words over a Finite Alphabet</a>, J. Int. Seq. 19 (2016) # 16.1.3, Example 11.
%H A255813 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (4,-3,3).
%F A255813 a(n+3) = 4*a(n+2) - 3*a(n+1)+ 3*a(n) with n>=0, a(0) = 1, a(1) = 3, a(2) = 10.
%F A255813 G.f.: (-1 + x - x^2)/(-1 + 4*x - 3*x^2 + 3*x^3). - _R. J. Mathar_, Nov 07 2015
%t A255813 RecurrenceTable[{a[0] == 1, a[1] == 3, a[2]== 10, a[n] == 4 a[n - 1] - 3 a[n - 2] + 3 a[n - 3]}, a[n], {n, 0, 25}]
%t A255813 LinearRecurrence[{4, -3, 3}, {1, 3, 10}, 100] (* _G. C. Greubel_, Jun 02 2016 *)
%Y A255813 Cf. A255116, A255118, A254658, A254660, A255633, A255630
%K A255813 nonn,easy
%O A255813 0,2
%A A255813 _Milan Janjic_, Mar 07 2015