%I #6 Dec 28 2023 23:45:19
%S 46,2116,42090,480236,3868968,24527068,129982953,597438379,2440360420,
%T 9014646324,30516683840,95673407206,280189387450,772054552094,
%U 2013904240777,4999298886201,11864241181898,27024721429998
%N Number of n X 4 0..2 arrays with rows, columns, diagonals and antidiagonals unimodal.
%C Column 4 of A223742.
%H R. H. Hardin, <a href="/A223738/b223738.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = (456419/5230697472000)*n^16 + (165527/653837184000)*n^15 + (6741457/261534873600)*n^14 + (1421311/18681062400)*n^13 + (7617457/4105728000)*n^12 + (19582007/1026432000)*n^11 - (63058463/1828915200)*n^10 + (1056206617/914457600)*n^9 + (19216393349/36578304000)*n^8 - (11500149887/326592000)*n^7 + (100418946673/205286400)*n^6 - (160502953561/51321600)*n^5 + (51589184233711/4036032000)*n^4 - (15461118743597/504504000)*n^3 + (18492215887/672672)*n^2 + (3967393411/90090)*n - 95767 for n>6.
%e Some solutions for n=3
%e ..1..1..1..0....1..0..0..0....0..0..2..1....0..1..2..2....1..0..0..0
%e ..2..2..2..1....0..1..2..2....1..1..2..0....0..0..1..2....2..2..2..0
%e ..2..0..0..0....0..0..2..2....1..0..0..0....0..0..1..2....2..2..2..1
%Y Cf. A223742.
%K nonn
%O 1,1
%A _R. H. Hardin_, Mar 26 2013
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