A219885 Number of 4Xn arrays of the minimum value of corresponding elements and their horizontal, diagonal or antidiagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 4Xn array.
15, 46, 146, 621, 2190, 6965, 21035, 60891, 171009, 465323, 1225425, 3124293, 7723032, 18545881, 43355303, 98866072, 220320615, 480589189, 1027625310, 2156754843, 4448124037, 9024377209, 18027331364, 35488683485, 68901443927
Offset: 1
Keywords
Examples
Some solutions for n=3 ..0..0..0....1..0..1....1..0..1....0..0..0....1..0..0....1..0..0....0..0..0 ..0..0..0....1..0..0....1..0..0....0..0..0....1..0..1....1..0..1....0..0..0 ..0..0..0....1..0..1....1..0..0....0..0..0....1..0..0....2..1..1....0..0..0 ..1..0..1....1..1..1....2..0..2....1..0..2....2..0..1....2..1..1....0..2..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..78
Formula
Empirical: a(n) = (1/15511210043330985984000000)*n^25 - (1/62044840173323943936000)*n^24 + (659/310224200866619719680000)*n^23 - (223/1348800873333129216000)*n^22 + (11969/1751689445887180800000)*n^21 + (13987/175168944588718080000)*n^20 - (307777/9016048618536960000)*n^19 + (218951/80669908692172800)*n^18 - (82167296539/645359269537382400000)*n^17 + (13594532843/3796230997278720000)*n^16 - (148582864867/5965505852866560000)*n^15 - (1842704639807/596550585286656000)*n^14 + (75084344850088337/417585409700659200000)*n^13 - (232073313496988597/41758540970065920000)*n^12 + (200770875484427393/1898115498639360000)*n^11 - (169860589360483739/189811549863936000)*n^10 - (86302000251116357611/5762136335155200000)*n^9 + (405525610427277793513/576213633515520000)*n^8 - (19180292378240586517013/1419192838103040000)*n^7 + (823632212233422499573/5256269770752000)*n^6 - (16853478306444036905959921/16261584603264000000)*n^5 + (8636807269422406550143/6022809112320000)*n^4 + (2309304917571323764033/58203617472000)*n^3 - (428371026518922607544/1159525191825)*n^2 + (1047154147978610871/743642900)*n - 2019003704 for n>23
Comments