Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #4 Jan 29 2015 19:51:39
%S 3372,35529,409051,4766957,54712559,630430184,7273310228,83838776143,
%T 966536400371,11143872854174,128479354314846,1481261635497821,
%U 17077855175576714,196894624081569751,2270044263780068047
%N Number of (n+2)X(2+2) 0..1 arrays with every 3X3 subblock diagonal maximum plus antidiagonal maximum nondecreasing horizontally, vertically and ne-to-sw antidiagonally
%C Column 2 of A254390
%H R. H. Hardin, <a href="/A254384/b254384.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 12*a(n-1) +5*a(n-2) -40*a(n-3) -881*a(n-4) -1730*a(n-5) +14033*a(n-6) +2668*a(n-7) -12716*a(n-8) -91324*a(n-9) +26296*a(n-10) +149802*a(n-11) -8770*a(n-12) +728*a(n-13) -76056*a(n-14) +848640*a(n-15) -1019978*a(n-16) -1367966*a(n-17) +887700*a(n-18) +112840*a(n-19) +2066789*a(n-20) +94674*a(n-21) -1572123*a(n-22) -324304*a(n-23) -1135827*a(n-24) +1289606*a(n-25) +771953*a(n-26) -793926*a(n-27) +108632*a(n-28) +76256*a(n-29) -51808*a(n-30) +4320*a(n-31) +2752*a(n-32) -256*a(n-33)
%e Some solutions for n=2
%e ..1..1..1..0....1..0..0..1....0..1..0..0....0..1..0..1....1..0..1..0
%e ..0..1..1..0....1..0..0..1....0..0..1..0....1..1..1..1....1..1..0..1
%e ..1..0..0..1....1..1..1..1....0..1..1..0....1..0..1..1....1..1..1..1
%e ..0..1..1..1....0..1..1..1....0..1..0..0....1..0..0..1....0..1..1..0
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 29 2015