A224265 Number of 5Xn 0..2 arrays with rows and antidiagonals unimodal and columns nondecreasing

21, 441, 5246, 41012, 238366, 1122522, 4542734, 16423026, 54399996, 167906334, 488545330, 1351296894, 3575548984, 9095336020, 22330458551, 53087335395, 122539314344, 275260139864, 602890604743, 1289688693983, 2698414556120

Offset

1,1

Comments

Row 5 of A224262

Links

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

Formula

Empirical: a(n) = (1/1379196149760000)*n^20 - (1/137919614976000)*n^19 + (293/304874938368000)*n^18 + (1/4619317248000)*n^17 + (157/352235520000)*n^16 + (8317/2092278988800)*n^15 + (2780521/20922789888000)*n^14 + (383809/213497856000)*n^13 + (203282759/6897623040000)*n^12 + (34268483/229920768000)*n^11 + (1734251209/357654528000)*n^10 + (5309275061/1609445376000)*n^9 + (4327647950569/17435658240000)*n^8 + (321770123/1257984000)*n^7 + (506327783081/101896704000)*n^6 - (990071393771/62270208000)*n^5 + (554590430608603/18525386880000)*n^4 - (8854141496479/77189112000)*n^3 + (188734999923373/97772875200)*n^2 - (257473009033/29099070)*n + 13615 for n>4

Example

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

Crossrefs

Sequence in context: A206880 A206997 A189613 * A206886 A188770 A223922

Adjacent sequences: A224262 A224263 A224264 * A224266 A224267 A224268

Keyword

nonn

Author

R. H. Hardin Apr 02 2013

Status

approved