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%I #6 Nov 09 2018 04:57:35
%S 9,37,215,1287,7673,45709,272417,1623601,9676571,57671897,343721665,
%T 2048564473,12209345763,72767112987,433688490081,2584762523789,
%U 15405060215819,91813417313133,547203547448227,3261306801365497
%N Number of (1+1)X(n+1) 0..2 arrays with every element both >= and <= some horizontal or antidiagonal neighbor
%C Row 1 of A232257
%H R. H. Hardin, <a href="/A232258/b232258.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 6*a(n-1) -3*a(n-2) +19*a(n-3) -16*a(n-4) +13*a(n-5) -45*a(n-6) -10*a(n-7) -26*a(n-8) -11*a(n-9) +26*a(n-10) +4*a(n-11) -4*a(n-12) for n>13.
%F Empirical g.f.: 9*x -x^2*(-37 +7*x -108*x^2 +107*x^3 -39*x^4 +312*x^5 +99*x^6 +173*x^7 +27*x^8 -184*x^9 -20*x^10 +28*x^11)/(x^3 -2*x^2 +x -1)/(4*x^9 +4*x^8 -22*x^7 -33*x^6 -14*x^5 -7*x^4 +12*x^3 +4*x^2 +5*x -1) . - _R. J. Mathar_, Nov 09 2018
%e Some solutions for n=7
%e ..0..0..1..1..1..2..0..0....0..0..1..1..0..2..0..0....0..0..1..1..2..2..1..1
%e ..0..0..1..2..2..1..0..0....2..2..1..0..2..0..2..2....2..2..2..2..0..0..2..2
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 21 2013
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