A224055 Number of nX6 0..2 arrays with rows and columns unimodal and antidiagonals nondecreasing.

148, 4690, 57911, 428949, 2392915, 11231300, 46853641, 179545949, 646161612, 2215310269, 7295294696, 23173431000, 71137228340, 211216789027, 606907100518, 1688654512840, 4553248388246, 11908977568334, 30245780813181

Offset: 1

Author

R. H. Hardin Mar 30 2013

Keywords

• nonn

Comments

Column 6 of A224057

Examples

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

Links

• R. H. Hardin, Table of n, a(n) for n = 1..178

Formula

Empirical: a(n) = (1/35608838483312640000)*n^24 + (1/593480641388544000)*n^23 + (1/11491439984640000)*n^22 + (59/20274183401472000)*n^21 + (204271/2432902008176640000)*n^20 + (34451/17377871486976000)*n^19 + (18917939/448166159400960000)*n^18 + (769849/995924798668800)*n^17 + (226679623/17575143505920000)*n^16 + (2152013/11412430848000)*n^15 + (706815667/289700167680000)*n^14 + (9710969/517321728000)*n^13 + (22058018740169/52725430517760000)*n^12 + (883262112781/878757175296000)*n^11 + (30292372315283/675967057920000)*n^10 + (425362282393/5977939968000)*n^9 + (18858448588311589/8002967132160000)*n^8 - (2707211596157/114328101888000)*n^7 + (2638894624680309119/59133034920960000)*n^6 - (590269621381831/6636704256000)*n^5 + (21039414018476657/25935541632000)*n^4 - (10575054526365457/1955457504000)*n^3 + (4363361309424841/172982779200)*n^2 + (520015184729/102965940)*n - 216272 for n>7