A219716 Number of 3Xn arrays of the minimum value of corresponding elements and their horizontal or antidiagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..3 3Xn array

20, 44, 297, 1751, 7862, 30452, 106421, 345175, 1059499, 3113829, 8821007, 24186180, 64368220, 166638599, 420428489, 1035522928, 2493797431, 5880625520, 13596111695, 30856241755, 68811371991, 150927167533, 325853157602

Offset

1,1

Comments

Row 3 of A219714

Links

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

Formula

Empirical: a(n) = (1/8401905440137617408000000)*n^26 - (1/64630041847212441600000)*n^25 + (107/155112100433309859840000)*n^24 + (1/23761044796769280000)*n^23 - (103/13233917517004800000)*n^22 + (1681/3005349539512320000)*n^21 - (807181/32267963476869120000)*n^20 + (3201449/4257578514309120000)*n^19 - (997337659/80669908692172800000)*n^18 - (632589611/2688996956405760000)*n^17 + (100650580631/2982752926433280000)*n^16 - (825235909/424789845480000)*n^15 + (13546857698161409/169644072690892800000)*n^14 - (1450780447643119/579979735695360000)*n^13 + (1247624255371401407/20879270485032960000)*n^12 - (41385606307935181/39544072888320000)*n^11 + (20084750476333849/1731411158400000)*n^10 - (20613489925124552999/1344498478202880000)*n^9 - (94689075182485664850649/38318206628782080000)*n^8 + (11206671056766215566519/187834346219520000)*n^7 - (121990800794493700512234947/146354261429376000000)*n^6 + (4581091125109590787891997/573938280115200000)*n^5 - (14361044875078954846102073/267154604196480000)*n^4 + (3109939899102790394890237/12467214862502400)*n^3 - (156299115694903226081/207244889280)*n^2 + (98999926083919027/74364290)*n - 1055987659 for n>18

Example

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

Crossrefs

Sequence in context: A211459 A256870 A134619 * A044097 A044478 A228319

Adjacent sequences: A219713 A219714 A219715 * A219717 A219718 A219719

Keyword

nonn

Author

R. H. Hardin Nov 26 2012

Status

approved