A223965 - OEIS

%I #6 Mar 25 2022 18:36:17

%S 1024,48620,485714,2575955,9779558,30643468,85350934,220335341,

%T 539722230,1270939682,2897487924,6419463692,13849588776,29130616029,

%U 59785815715,119811736276,234625138625,449330010578,842238087946,1546539992378

%N Number of 5 X n 0..3 arrays with antidiagonals unimodal and rows and diagonals nondecreasing.

%C Row 5 of A223961.

%H R. H. Hardin, <a href="/A223965/b223965.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = (1/217728000)*n^15 + (1/7257600)*n^14 + (1021/283046400)*n^13 + (89/1267200)*n^12 + (49747/42768000)*n^11 + (114077/7257600)*n^10 + (4197611/21772800)*n^9 + (2072933/1036800)*n^8 + (4176906623/217728000)*n^7 + (25808249/172800)*n^6 + (198423611/194400)*n^5 + (1908980977/453600)*n^4 + (19380549743/4536000)*n^3 - (3498352713/30800)*n^2 + (12988213717/90090)*n + 329692 for n>8.

%e Some solutions for n=3

%e ..0..0..0....0..0..2....0..0..0....0..0..3....0..0..2....0..0..0....0..0..3

%e ..0..0..0....2..2..3....2..2..2....0..2..3....0..0..0....0..0..0....0..0..0

%e ..1..2..2....0..2..3....1..2..3....1..1..2....0..2..2....0..0..1....0..0..3

%e ..0..2..3....1..2..3....1..1..2....0..2..2....0..0..3....0..2..2....0..1..3

%e ..0..3..3....0..2..2....1..1..3....1..2..2....0..2..3....2..2..2....0..1..2

%Y Cf. A223961.

%K nonn

%O 1,1

%A _R. H. Hardin_, Mar 29 2013