A224206 Number of 4Xn 0..3 arrays with rows unimodal and antidiagonals nondecreasing

256, 16000, 263516, 2411246, 16355242, 93052770, 475218035, 2252100875, 10026501335, 42033573628, 165872759545, 616278459399, 2159074455116, 7151151269790, 22464417502819, 67161353094487, 191751351630146

Offset

1,1

Comments

Row 4 of A224204

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = (1/2906843957821440000)*n^24 + (11/242236996485120000)*n^23 + (4897/1529252690853888000)*n^22 + (2857/19308746096640000)*n^21 + (973909/198604245565440000)*n^20 + (93229/757205729280000)*n^19 + (266789/109442285568000)*n^18 + (104478641/2667655710720000)*n^17 + (1429093157/2738983403520000)*n^16 + (4913895191/836911595520000)*n^15 + (171672001139/3012881743872000)*n^14 + (29350223359/59779399680000)*n^13 + (433008014137969/110472330608640000)*n^12 + (76105242218503/2510734786560000)*n^11 + (344040677347481/1506440871936000)*n^10 + (4054053159749/2583060480000)*n^9 + (276889384664596819/32011868528640000)*n^8 + (4163175202299941/127031224320000)*n^7 + (2967972507533347/42533251891200)*n^6 + (338490515487987437/4223788208640000)*n^5 + (85995749191634941/527973526080000)*n^4 - (9502462212673/345080736000)*n^3 - (23527482078379273/74209612276800)*n^2 + (572648006969/535422888)*n - 1055 for n>2

Example

Some solutions for n=3
..1..0..0....0..2..2....0..0..2....0..0..0....2..2..2....2..2..0....0..2..1
..3..2..1....3..2..1....3..2..0....3..2..1....2..2..0....3..0..0....3..3..0
..2..2..3....2..1..1....3..1..1....3..2..1....2..2..2....3..2..0....3..2..0
..3..3..3....1..2..3....3..3..3....2..2..3....2..2..2....2..2..3....2..2..1

Crossrefs

Sequence in context: A136286 A269204 A224283 * A238064 A235964 A206319

Adjacent sequences: A224203 A224204 A224205 * A224207 A224208 A224209

Keyword

nonn

Author

R. H. Hardin Apr 01 2013

Status

approved