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Number of (n+2)X5 0..2 arrays with each 3X3 subblock having rows and columns in lexicographically nondecreasing order
1

%I #5 Mar 31 2012 12:36:01

%S 13659,76309,308692,1043186,3097348,8297059,20411234,46732687,

%T 100636591,205574323,401123377,751921908,1360579387,2385984676,

%U 4068843506,6766785098,11002001311,17525142877,27400120766,42115574722,63730107482

%N Number of (n+2)X5 0..2 arrays with each 3X3 subblock having rows and columns in lexicographically nondecreasing order

%C Column 3 of A185477

%H R. H. Hardin, <a href="/A185471/b185471.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n) = (1/444787200)*n^13

%F + (107/479001600)*n^12

%F + (11/1088640)*n^11

%F + (3623/6220800)*n^10

%F + (78227/3628800)*n^9

%F + (6420917/14515200)*n^8

%F + (148481/27216)*n^7

%F + (1861160843/43545600)*n^6

%F + (4966108109/21772800)*n^5

%F + (1448539279/1555200)*n^4

%F + (3663351401/1330560)*n^3

%F + (2013261953/415800)*n^2

%F + (15650889/3640)*n

%F + 556

%e Some solutions for 4X5

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 28 2011