A224053 Number of n X 4 0..2 arrays with rows and columns unimodal and antidiagonals nondecreasing.

46, 698, 5219, 27246, 115716, 428949, 1442005, 4492529, 13133871, 36307595, 95412314, 239342404, 575169570, 1328404782, 2957341785, 6363295591, 13266197675, 26858140315, 52913319943, 101631438086, 190636635796

Offset

1,1

Comments

Column 4 of A224057.

Links

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

Formula

Empirical: a(n) = (1/106748928000)*n^16 + (1/2668723200)*n^15 + (29/2335132800)*n^14 + (9677/37362124800)*n^13 + (129359/28740096000)*n^12 + (171629/2874009600)*n^11 + (12139/18662400)*n^10 + (195851/37324800)*n^9 + (231935077/5225472000)*n^8 + (74110763/261273600)*n^7 + (324341569/179625600)*n^6 + (4052978161/718502400)*n^5 + (3589053277/247104000)*n^4 - (12388141/741312)*n^3 + (87129737/1029600)*n^2 + (364945/2574)*n - 457 for n>3.

Example

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

Crossrefs

Cf. A224057.

Sequence in context: A160151 A278204 A223929 * A224306 A224370 A078156

Adjacent sequences: A224050 A224051 A224052 * A224054 A224055 A224056

Keyword

nonn

Author

R. H. Hardin, Mar 30 2013

Status

approved