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%I #4 Mar 30 2013 10:18:44
%S 256,10000,112436,772683,4002738,16861106,60614473,192152734,
%T 549805730,1444560196,3531148666,8113219067,17664791690,36688857572,
%U 73086084181,140275448000,260397984212,469049039484,822128311864,1405576043323
%N Number of 4Xn 0..3 arrays with rows nondecreasing and antidiagonals unimodal
%C Row 4 of A224024
%H R. H. Hardin, <a href="/A224026/b224026.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = (3551/47900160)*n^12 + (89357/39916800)*n^11 + (787537/21772800)*n^10 + (54391/145152)*n^9 + (3628073/1451520)*n^8 + (219389/19200)*n^7 + (790310011/21772800)*n^6 + (11979533/145152)*n^5 + (26980967/217728)*n^4 + (119696723/907200)*n^3 + (46358119/831600)*n^2 + (56717/396)*n + 52 for n>2
%e Some solutions for n=3
%e ..0..0..3....0..2..2....0..1..1....0..1..1....1..1..3....0..2..3....0..1..3
%e ..0..2..2....1..1..1....0..0..3....2..2..3....2..2..3....3..3..3....0..2..3
%e ..2..3..3....0..0..0....0..0..2....0..3..3....0..2..3....0..2..2....2..2..2
%e ..0..0..1....0..1..2....0..2..2....1..3..3....0..2..2....1..3..3....0..1..3
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 30 2013
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