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A253320 Number of (n+1)X(2+1) 0..1 arrays with every 2X2 subblock sum nondecreasing horizontally, vertically and antidiagonally ne-to-sw 1

%I

%S 44,126,377,848,2042,4218,9228,18482,38621,76654,156631,310658,627864,

%T 1247558,2507954,4993614,10012411,19968402,39986317,79836334,

%U 159770246,319221314,638635272,1276539506,2553459769,5105272678,10211298371

%N Number of (n+1)X(2+1) 0..1 arrays with every 2X2 subblock sum nondecreasing horizontally, vertically and antidiagonally ne-to-sw

%C Column 2 of A253326

%H R. H. Hardin, <a href="/A253320/b253320.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 4*a(n-1) +2*a(n-2) -26*a(n-3) +16*a(n-4) +62*a(n-5) -70*a(n-6) -62*a(n-7) +109*a(n-8) +14*a(n-9) -76*a(n-10) +16*a(n-11) +20*a(n-12) -8*a(n-13)

%e Some solutions for n=4

%e ..1..0..1....0..1..0....0..1..0....1..0..1....1..0..1....0..0..0....1..0..0

%e ..0..1..0....0..0..0....0..0..0....0..0..0....0..0..0....0..1..1....0..0..1

%e ..1..0..1....0..1..0....1..0..1....0..1..0....0..1..0....1..1..1....1..0..1

%e ..0..1..0....1..1..1....0..1..0....0..0..0....1..1..1....1..1..1....0..1..0

%e ..1..0..1....1..1..1....1..1..1....1..1..1....0..1..0....1..1..1....0..1..1

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 30 2014

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Last modified September 30 08:55 EDT 2022. Contains 357104 sequences. (Running on oeis4.)