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A223921 Number of 4Xn 0..2 arrays with rows and antidiagonals unimodal and columns nondecreasing 1

%I

%S 15,225,2111,14123,74040,323394,1226491,4157102,12856218,36834899,

%T 98904313,251078009,606789828,1403779390,3122765753,6704628063,

%U 13936852281,28123662137,55220811463,105715542647,197678421680

%N Number of 4Xn 0..2 arrays with rows and antidiagonals unimodal and columns nondecreasing

%C Row 4 of A223918

%H R. H. Hardin, <a href="/A223921/b223921.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = (1/106748928000)*n^16 + (1/2668723200)*n^15 + (29/2335132800)*n^14 + (10013/37362124800)*n^13 + (133979/28740096000)*n^12 + (37333/574801920)*n^11 + (49631/65318400)*n^10 + (1761593/261273600)*n^9 + (219704797/5225472000)*n^8 + (49791911/261273600)*n^7 + (925916249/1437004800)*n^6 + (287406331/179625600)*n^5 + (44691980741/15567552000)*n^4 + (315864449/86486400)*n^3 + (14884357/4324320)*n^2 + (558703/360360)*n + 1

%e Some solutions for n=3

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Mar 29 2013

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Last modified July 6 14:10 EDT 2022. Contains 355110 sequences. (Running on oeis4.)