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 A222937 #6 Jul 23 2025 03:17:53 %S A222937 8,64,512,4000,32760,262104,2097152,16777216,134217728,1073741824, %T A222937 8589499198,68719476736,549755813888,4398046511104,35184372088832, %U A222937 281474975268864,2251799813683712,18014398509056000,144115188075855872 %N A222937 Sum of neighbor maps: number of 3Xn binary arrays indicating the locations of corresponding elements equal to the sum mod 4 of their horizontal and antidiagonal neighbors in a random 0..3 3Xn array. %C A222937 Row 3 of A222935 %H A222937 R. H. Hardin, <a href="/A222937/b222937.txt">Table of n, a(n) for n = 1..184</a> %e A222937 Some solutions for n=3 %e A222937 ..0..0..0....1..0..1....0..1..1....0..0..1....0..0..1....0..1..1....1..1..0 %e A222937 ..0..0..0....0..0..0....0..1..1....1..1..1....0..0..1....1..0..1....0..0..0 %e A222937 ..1..0..0....1..0..1....0..0..0....0..0..1....1..1..1....0..0..0....0..0..0 %K A222937 nonn %O A222937 1,1 %A A222937 _R. H. Hardin_ Mar 09 2013