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%I #4 Jun 28 2012 08:08:14
%S 5314,1299735,74323976,1839121115,26346319032,256652587891,
%T 1876235252048,10982618599248,53844488576650,228411366730514,
%U 858979624713168,2917594805354242,9082065855050720,26213547883869330,70820298142121408
%N Number of 4X4 0..n matrices with row and column 1..4 having sum <= i*n
%C Row 4 of A213962
%H R. H. Hardin, <a href="/A213964/b213964.txt">Table of n, a(n) for n = 1..41</a>
%F Empirical: a(n) = (4679471/2270268000)*n^16 + (135958687/2476656000)*n^15 + (2078860429/3113510400)*n^14 + (2558219003/518918400)*n^13 + (274698527/11088000)*n^12 + (481269659/5346000)*n^11 + (18685736999/76204800)*n^10 + (19501561159/38102400)*n^9 + (22571956991/27216000)*n^8 + (1057766063/1008000)*n^7 + (82705488571/79833600)*n^6 + (1231373209/1555200)*n^5 + (3137244260567/6810804000)*n^4 + (299434637471/1513512000)*n^3 + (51361787/864864)*n^2 + (268615/24024)*n + 1
%e Some solutions for n=4
%e ..3..0..1..0....1..3..0..0....3..0..0..0....1..3..0..0....4..0..0..0
%e ..1..2..0..3....0..4..2..1....0..4..3..0....3..4..0..0....0..4..0..4
%e ..0..3..1..2....0..1..0..1....0..3..1..4....0..1..3..3....0..1..2..4
%e ..0..2..1..0....1..0..4..0....0..0..0..4....0..0..4..4....0..1..2..4
%K nonn
%O 1,1
%A _R. H. Hardin_ Jun 28 2012
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