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Number of (n+1)X(2+1) 0..2 arrays with every 2X2 subblock summing to a prime and those sums nondecreasing in every row and column
1

%I #4 Dec 02 2014 18:44:37

%S 168,738,3142,11134,38509,120982,373380,1094071,3155436,8863194,

%T 24492702,66982908,179947523,483592878,1274228592,3384152417,

%U 8795160858,23166886746,59604866106,156072942342,398500362769,1038849541150

%N Number of (n+1)X(2+1) 0..2 arrays with every 2X2 subblock summing to a prime and those sums nondecreasing in every row and column

%C Column 2 of A251467

%H R. H. Hardin, <a href="/A251461/b251461.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) +49*a(n-2) -153*a(n-3) -1104*a(n-4) +3618*a(n-5) +15150*a(n-6) -52686*a(n-7) -141261*a(n-8) +529155*a(n-9) +943809*a(n-10) -3889737*a(n-11) -4629634*a(n-12) +21668376*a(n-13) +16696000*a(n-14) -93424752*a(n-15) -42911136*a(n-16) +315582912*a(n-17) +69542304*a(n-18) -839792736*a(n-19) -26831424*a(n-20) +1760079744*a(n-21) -210739200*a(n-22) -2887941888*a(n-23) +704317184*a(n-24) +3662932224*a(n-25) -1270489856*a(n-26) -3514394880*a(n-27) +1522300416*a(n-28) +2461888512*a(n-29) -1246003200*a(n-30) -1185767424*a(n-31) +673726464*a(n-32) +350355456*a(n-33) -217645056*a(n-34) -47775744*a(n-35) +31850496*a(n-36)

%e Some solutions for n=4

%e ..0..2..0....1..0..1....1..1..1....1..0..1....1..0..1....1..0..2....1..0..0

%e ..0..1..2....0..1..0....0..0..1....1..0..1....2..0..2....0..1..0....1..0..2

%e ..1..1..1....0..2..0....1..1..1....0..1..0....1..0..1....0..2..0....1..0..0

%e ..2..1..2....1..0..1....1..0..1....1..0..2....0..2..2....1..0..1....0..1..1

%e ..2..2..2....2..2..2....0..2..2....0..1..2....2..1..0....0..2..2....0..1..0

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 02 2014