cp's OEIS Frontend

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.

A229843 Number of nX4 0..2 arrays x(i,j) with each element horizontally or vertically next to at least one element with value 2-x(i,j).

This page as a plain text file.
%I A229843 #6 Jun 02 2025 08:38:56
%S A229843 9,423,13401,453837,15269193,514371027,17324310663,583513743897,
%T A229843 19653679602141,661968066724119,22296164158938861,750971189107675233,
%U A229843 25293934916476773699,851940997449956765547,28694762814404871782187
%N A229843 Number of nX4 0..2 arrays x(i,j) with each element horizontally or vertically next to at least one element with value 2-x(i,j).
%C A229843 Column 4 of A229847
%H A229843 R. H. Hardin, <a href="/A229843/b229843.txt">Table of n, a(n) for n = 1..210</a>
%F A229843 Empirical: a(n) = 28*a(n-1) +223*a(n-2) -810*a(n-3) -8714*a(n-4) -856*a(n-5) +147241*a(n-6) +236084*a(n-7) -1172242*a(n-8) -3528345*a(n-9) +678458*a(n-10) +16652175*a(n-11) +101500683*a(n-12) -128462366*a(n-13) -411090364*a(n-14) +905075331*a(n-15) -2603919959*a(n-16) +5803974821*a(n-17) -7111289023*a(n-18) +9684239810*a(n-19) -13438664953*a(n-20) +15373544589*a(n-21) -17181774335*a(n-22) +14938323369*a(n-23) -15592749244*a(n-24) +3820796842*a(n-25) +4237587780*a(n-26) -3292600679*a(n-27) +15021433542*a(n-28) -4461452087*a(n-29) -11101458512*a(n-30) +37414533509*a(n-31) -67227775904*a(n-32) +83523691644*a(n-33) -116673702936*a(n-34) +124723830770*a(n-35) -123437354031*a(n-36) +134526294777*a(n-37) -110378277541*a(n-38) +89122202017*a(n-39) -80590207954*a(n-40) +64320664361*a(n-41) -49928847307*a(n-42) +30705120692*a(n-43) -25484291913*a(n-44) +22612424455*a(n-45) -10724796799*a(n-46) +6043765216*a(n-47) -4421780238*a(n-48) +2556973448*a(n-49) -1102876952*a(n-50) +274132088*a(n-51) -116104448*a(n-52) -5874816*a(n-53)
%e A229843 Some solutions for n=3
%e A229843 ..2..0..2..0....2..0..2..1....2..1..1..0....2..0..2..0....1..1..1..1
%e A229843 ..2..2..2..2....1..0..0..1....0..0..2..2....0..0..2..1....2..0..2..0
%e A229843 ..0..0..0..2....1..2..2..0....2..2..0..2....1..1..0..1....2..0..0..2
%K A229843 nonn
%O A229843 1,1
%A A229843 _R. H. Hardin_, Oct 01 2013