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 A219409 #6 Jul 23 2025 00:25:44 %S A219409 37,4523,398375,35794147,3227238239,290895472306,26219581585508, %T A219409 2363313103579962,213017529066100563,19200373208853887323, %U A219409 1730628931949055584941,155990537505981270461154 %N A219409 Unmatched value maps: number of nX7 binary arrays indicating the locations of corresponding elements not equal to any horizontal or antidiagonal neighbor in a random 0..2 nX7 array. %C A219409 Column 7 of A219410 %H A219409 R. H. Hardin, <a href="/A219409/b219409.txt">Table of n, a(n) for n = 1..123</a> %F A219409 Empirical: a(n) = 37*a(n-1) +3825*a(n-2) +81558*a(n-3) +510200*a(n-4) -2139740*a(n-5) -24964195*a(n-6) +44570360*a(n-7) +423494493*a(n-8) -1028219843*a(n-9) -2247233985*a(n-10) +9983856169*a(n-11) -7627675319*a(n-12) -13359810842*a(n-13) +28791113562*a(n-14) -18765233198*a(n-15) +2128700109*a(n-16) +2355058186*a(n-17) -585137197*a(n-18) -134608755*a(n-19) +39387120*a(n-20) +3106800*a(n-21) -864000*a(n-22) for n>24 %e A219409 Some solutions for n=3 %e A219409 ..0..0..1..0..0..0..0....0..0..1..1..0..1..1....0..0..0..1..1..0..0 %e A219409 ..0..0..1..0..1..0..0....0..0..0..0..0..0..1....0..1..0..0..0..1..0 %e A219409 ..0..1..1..0..0..1..1....1..0..1..0..1..0..0....1..1..0..0..1..0..1 %K A219409 nonn %O A219409 1,1 %A A219409 _R. H. Hardin_ Nov 19 2012