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A251803 Number of (3+1)X(n+1) 0..3 arrays with no 2X2 subblock having x11-x00 less than x10-x01.

%I A251803 #6 Jun 02 2025 10:32:32
%S A251803 19269,724300,17195593,294088336,3934266515,43510308650,413630526506,
%T A251803 3478117057808,26433809155056,184631083973492,1200862969509714,
%U A251803 7350360178000790,42705102555064986,237181196199079904
%N A251803 Number of (3+1)X(n+1) 0..3 arrays with no 2X2 subblock having x11-x00 less than x10-x01.
%C A251803 Row 3 of A251801
%H A251803 R. H. Hardin, <a href="/A251803/b251803.txt">Table of n, a(n) for n = 1..210</a>
%F A251803 Empirical: a(n) = 70*a(n-1) -2375*a(n-2) +52042*a(n-3) -827990*a(n-4) +10195132*a(n-5) -101124322*a(n-6) +830421108*a(n-7) -5758451859*a(n-8) +34223487178*a(n-9) -176332070653*a(n-10) +794779755110*a(n-11) -3156457476820*a(n-12) +11109873120920*a(n-13) -34818233254780*a(n-14) +97527763758712*a(n-15) -244892909297175*a(n-16) +552543768062970*a(n-17) -1122181309818449*a(n-18) +2053995521193590*a(n-19) -3390759101221990*a(n-20) +5049772850347484*a(n-21) -6783271969135666*a(n-22) +8213149434578420*a(n-23) -8953247189169461*a(n-24) +8772430272272310*a(n-25) -7708025280163467*a(n-26) +6055906423103258*a(n-27) -4238615566223888*a(n-28) +2630732733430288*a(n-29) -1439628171650384*a(n-30) +689679083321824*a(n-31) -286667447021696*a(n-32) +102211164419072*a(n-33) -30802911196416*a(n-34) +7693171914240*a(n-35) -1549479297024*a(n-36) +241805316096*a(n-37) -27432235008*a(n-38) +2012553216*a(n-39) -71663616*a(n-40)
%e A251803 Some solutions for n=1
%e A251803 ..0..3....1..2....3..1....3..2....2..1....1..3....0..0....0..0....3..2....0..3
%e A251803 ..2..1....0..0....0..2....0..1....1..2....3..3....3..3....2..2....2..3....0..0
%e A251803 ..2..3....0..1....0..0....3..3....0..3....1..3....0..3....2..3....0..3....0..3
%e A251803 ..0..1....0..3....2..2....0..2....2..0....3..2....3..3....2..1....2..0....1..3
%K A251803 nonn
%O A251803 1,1
%A A251803 _R. H. Hardin_, Dec 09 2014