A224395 Number of 6Xn 0..3 arrays with diagonals and antidiagonals unimodal and rows nondecreasing.

4096, 1000000, 18794636, 152271025, 879830242, 4364554008, 19879000458, 84675848787, 337896379016, 1262027034092, 4414609771988, 14497401758306, 44849313719663, 131213360082438, 364483316826362, 964981060109623

Offset: 1

Author

R. H. Hardin Apr 05 2013

Keywords

• nonn

Comments

Row 6 of A224391

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..96

Formula

Empirical: a(n) = (42587101/1600593426432000)*n^18 + (83940121/177843714048000)*n^17 + (351548291/31384184832000)*n^16 + (404522743/2615348736000)*n^15 + (2603179801/1426553856000)*n^14 + (13975516589/747242496000)*n^13 + (1018677008761/3621252096000)*n^12 - (71772294491/67060224000)*n^11 + (9590385658061/219469824000)*n^10 - (19294207174217/73156608000)*n^9 + (6061000683461531/2414168064000)*n^8 - (67636294337629/7185024000)*n^7 + (580563104944166119/11769069312000)*n^6 + (14843452118300317/653837184000)*n^5 - (42702408306785177/59439744000)*n^4 + (14422633437701933/3027024000)*n^3 - (272645035897423741/15437822400)*n^2 + (10375478018905/1225224)*n + 82732433 for n>10