A219688 Number of 4Xn arrays of the minimum value of corresponding elements and their horizontal, vertical or antidiagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 4Xn array.
10, 19, 99, 427, 1531, 5031, 15763, 47784, 140586, 401745, 1116450, 3022129, 7979699, 20573716, 51835099, 127704345, 307858090, 726741861, 1681297548, 3815152314, 8498764539, 18601381870, 40034714647, 84794977698, 176874740063
Offset: 1
Keywords
Examples
Some solutions for n=3 ..1..1..0....2..0..0....0..0..0....1..1..0....2..1..1....1..0..0....1..0..0 ..1..0..0....2..0..0....0..0..0....1..0..0....2..1..1....1..0..0....1..0..0 ..2..0..0....2..1..1....1..0..0....1..0..0....2..2..2....1..0..0....1..1..1 ..2..1..1....2..1..1....1..2..2....2..2..2....2..2..2....2..1..1....1..1..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..125
Formula
Empirical: a(n) = (1/71811157608013824000000)*n^25 - (101/17234677825923317760000)*n^24 + (5449/4308669456480829440000)*n^23 - (68021/374666909259202560000)*n^22 + (9824237/510909421717094400000)*n^21 - (21583/13610640605184000)*n^20 + (5371647499/51090942171709440000)*n^19 - (394323599/68948639907840000)*n^18 + (45438295453/175751435059200000)*n^17 - (16515462281/1687213776568320)*n^16 + (542084002355513/1739939207086080000)*n^15 - (28192245777209/3381806039040000)*n^14 + (3250324207416831463/17399392070860800000)*n^13 - (1612171294329183241/463983788556288000)*n^12 + (2781152508058068181/52725430517760000)*n^11 - (757894220102779469/1198305239040000)*n^10 + (37334585059613913334793/6722492391014400000)*n^9 - (107120698751683891/3939922280448)*n^8 - (79214526965365782185939/798295971432960000)*n^7 + (49706772664271871813409/13646084981760000)*n^6 - (2005940155459581015843920483/48784753809792000000)*n^5 + (15777623834516738464154783/54205282010880000)*n^4 - (17331604984082844755616061/12467214862502400)*n^3 + (215362834119633956818141/49473074851200)*n^2 - (4207251609878775049/524924400)*n + 6438609162 for n>14
Comments