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 A212228 #6 Jun 02 2025 07:55:29 %S A212228 3834,10002,26637,71427,191853,514687,1376128,3659968,9662878, %T A212228 25562476,67800449,180120882,478897973,1273545563,3386125989, %U A212228 8999257525,23906208533,63493578634,168644397152,447996097328,1190222549456 %N A212228 Number of 0..2 arrays of length n+7 with sum no more than 8 in any length 8 subsequence (=50% duty cycle). %C A212228 Column 4 of A212232 %H A212228 R. H. Hardin, <a href="/A212228/b212228.txt">Table of n, a(n) for n = 1..210</a> %e A212228 Some solutions for n=3 %e A212228 ..0....0....0....0....1....2....2....0....0....2....2....1....1....0....1....0 %e A212228 ..1....2....0....1....0....1....0....1....1....2....0....2....2....2....1....0 %e A212228 ..1....0....0....1....0....1....1....2....0....1....1....0....0....0....1....0 %e A212228 ..1....0....2....0....1....0....0....0....1....0....1....1....0....0....2....1 %e A212228 ..2....0....2....0....0....0....1....0....1....0....2....0....1....1....0....0 %e A212228 ..1....1....0....0....1....1....2....2....2....1....0....2....2....0....1....1 %e A212228 ..2....2....0....1....1....2....0....2....0....1....0....2....1....0....1....0 %e A212228 ..0....1....2....1....0....0....2....0....1....1....0....0....1....1....0....0 %e A212228 ..0....1....2....1....0....2....1....1....1....2....1....1....1....1....1....2 %e A212228 ..0....2....0....2....2....0....0....0....2....2....1....2....0....1....0....2 %K A212228 nonn %O A212228 1,1 %A A212228 _R. H. Hardin_ May 06 2012