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 A245957 #6 Jul 23 2025 11:30:42 %S A245957 548,31577,300304,2141609,7972932,26526337,67596992,161991665, %T A245957 335832580,669329801,1217929488,2155659097,3584230244,5837790449, %U A245957 9084731392,13912683617,20579766372,30053056825,42704873360,60046213001,82587911428 %N A245957 Number of length 7+3 0..n arrays with some pair in every consecutive four terms totalling exactly n. %C A245957 Row 7 of A245950 %H A245957 R. H. Hardin, <a href="/A245957/b245957.txt">Table of n, a(n) for n = 1..210</a> %F A245957 Empirical: a(n) = 2*a(n-1) +5*a(n-2) -12*a(n-3) -9*a(n-4) +30*a(n-5) +5*a(n-6) -40*a(n-7) +5*a(n-8) +30*a(n-9) -9*a(n-10) -12*a(n-11) +5*a(n-12) +2*a(n-13) -a(n-14) %e A245957 Some solutions for n=2 %e A245957 ..1....2....2....2....2....1....0....1....1....2....2....0....0....2....1....1 %e A245957 ..0....0....1....1....2....1....2....1....2....0....1....2....2....0....2....0 %e A245957 ..0....1....2....1....0....0....2....1....0....2....0....1....2....2....0....1 %e A245957 ..1....2....0....0....1....2....0....1....1....0....1....1....2....0....2....0 %e A245957 ..2....0....0....0....2....0....2....2....0....2....0....1....0....0....1....2 %e A245957 ..1....2....2....1....2....0....1....1....2....1....2....0....1....2....2....2 %e A245957 ..2....2....0....2....1....2....2....2....0....0....1....1....0....1....0....2 %e A245957 ..0....0....2....1....1....0....1....1....2....1....0....0....1....1....2....0 %e A245957 ..0....2....1....1....0....1....2....1....2....1....2....2....2....2....0....1 %e A245957 ..0....2....2....0....1....2....1....0....1....2....2....2....0....0....2....1 %K A245957 nonn %O A245957 1,1 %A A245957 _R. H. Hardin_, Aug 08 2014