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 A100316 #24 Feb 09 2023 21:58:08 %S A100316 1,16,24,34,48,70,108,178,312,574,1092,2122,4176,8278,16476,32866, %T A100316 65640,131182,262260,524410,1048704,2097286,4194444,8388754,16777368, %U A100316 33554590,67109028,134217898,268435632,536871094,1073742012,2147483842,4294967496,8589934798 %N A100316 Number of 4 X n 0-1 matrices avoiding simultaneously the right angled numbered polyomino patterns (ranpp) (00;1), (01;0), (10;0) and (01;1). %C A100316 An occurrence of a ranpp (xy;z) in a matrix A=(a(i,j)) is a triple (a(i1,j1), a(i1,j2), a(i2,j1)) where i1 < i2, j1 < j2 and these elements are in the same relative order as those in the triple (x,y,z). In general, the number of m X n 0-1 matrices in question is given by 2^m + 2^n + 2*(n*m-n-m). %H A100316 G. C. Greubel, <a href="/A100316/b100316.txt">Table of n, a(n) for n = 0..1000</a> %H A100316 Sergey Kitaev, <a href="http://www.emis.de/journals/INTEGERS/papers/e21/e21.Abstract.html">On multi-avoidance of right angled numbered polyomino patterns</a>, Integers: Electronic Journal of Combinatorial Number Theory 4 (2004), A21, 20pp. %H A100316 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (4,-5,2). %F A100316 a(n) = 2^n + 6*n + 8 for n>0, a(0) = 1. %F A100316 G.f.: (1+12*x-35*x^2+16*x^3)/((1-2*x)*(1-x)^2). - _Alois P. Heinz_, Dec 21 2018 %F A100316 E.g.f.: exp(2*x) + 2*(4+3*x)*exp(x) - 8. - _G. C. Greubel_, Feb 01 2023 %t A100316 Table[If[n==0, 1, 2^n+6*n+8], {n,0,50}] (* _Vladimir Joseph Stephan Orlovsky_, Jul 08 2011 *) %o A100316 (Magma) [2^n+6*n+8*(1-0^n): n in [0..40]]; // _G. C. Greubel_, Feb 01 2023 %o A100316 (SageMath) [2^n+6*n+8*(1-0^n) for n in range(41)] # _G. C. Greubel_, Feb 01 2023 %Y A100316 Cf. A100314 (m=2), A100315 (m=3), this sequence (m=4). %K A100316 nonn %O A100316 0,2 %A A100316 _Sergey Kitaev_, Nov 13 2004 %E A100316 a(0)=1 prepended by _Alois P. Heinz_, Dec 21 2018