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A185470 Number of (n+2)X4 0..2 arrays with each 3X3 subblock having rows and columns in lexicographically nondecreasing order.

%I A185470 #7 Jul 22 2025 09:47:57
%S A185470 4594,21834,76309,225672,594798,1433903,3212372,6763143,13496424,
%T A185470 25706057,46997040,82868632,141494158,234746166,379524035,599450565,
%U A185470 927014574,1406248164,2096040183,3074201592,4442414038,6332210033
%N A185470 Number of (n+2)X4 0..2 arrays with each 3X3 subblock having rows and columns in lexicographically nondecreasing order.
%C A185470 Column 2 of A185477
%H A185470 R. H. Hardin, <a href="/A185470/b185470.txt">Table of n, a(n) for n = 1..200</a>
%F A185470 Empirical: a(n) = (1/9979200)*n^11
%F A185470 + (29/3628800)*n^10
%F A185470 + (257/241920)*n^9
%F A185470 + (4621/120960)*n^8
%F A185470 + (400927/604800)*n^7
%F A185470 + (1134257/172800)*n^6
%F A185470 + (31386443/725760)*n^5
%F A185470 + (20355493/90720)*n^4
%F A185470 + (80111509/100800)*n^3
%F A185470 + (40459121/25200)*n^2
%F A185470 + (7603747/4620)*n
%F A185470 + 273
%e A185470 Some solutions for 6X4
%e A185470 ..0..0..0..0....0..0..0..0....0..0..0..1....0..0..0..0....0..0..0..0
%e A185470 ..0..0..0..1....0..0..0..1....0..0..0..1....0..0..0..2....0..0..0..1
%e A185470 ..0..0..1..1....0..0..1..2....0..0..0..2....0..0..1..1....0..0..0..1
%e A185470 ..0..0..1..2....0..0..1..2....0..0..1..2....1..1..2..2....0..0..1..1
%e A185470 ..0..0..1..2....0..1..1..1....0..1..2..1....1..2..1..2....0..1..0..1
%e A185470 ..0..0..2..1....1..1..2..1....1..2..2..1....1..2..2..0....2..2..2..1
%K A185470 nonn
%O A185470 1,1
%A A185470 _R. H. Hardin_ Jan 28 2011