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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.

%I A219885 #6 Jul 23 2025 00:46:03
%S A219885 15,46,146,621,2190,6965,21035,60891,171009,465323,1225425,3124293,
%T A219885 7723032,18545881,43355303,98866072,220320615,480589189,1027625310,
%U A219885 2156754843,4448124037,9024377209,18027331364,35488683485,68901443927
%N 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.
%C A219885 Row 4 of A219883
%H A219885 R. H. Hardin, <a href="/A219885/b219885.txt">Table of n, a(n) for n = 1..78</a>
%F A219885 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
%e A219885 Some solutions for n=3
%e A219885 ..0..0..0....1..0..1....1..0..1....0..0..0....1..0..0....1..0..0....0..0..0
%e A219885 ..0..0..0....1..0..0....1..0..0....0..0..0....1..0..1....1..0..1....0..0..0
%e A219885 ..0..0..0....1..0..1....1..0..0....0..0..0....1..0..0....2..1..1....0..0..0
%e A219885 ..1..0..1....1..1..1....2..0..2....1..0..2....2..0..1....2..1..1....0..2..0
%K A219885 nonn
%O A219885 1,1
%A A219885 _R. H. Hardin_ Nov 30 2012