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A219818
Number of 4Xn arrays of the minimum value of corresponding elements and their horizontal, vertical or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 4Xn array
1
10, 33, 169, 648, 2179, 7049, 22017, 65842, 188487, 519028, 1381594, 3567948, 8961630, 21932971, 52387683, 122289966, 279347375, 625196496, 1372463293, 2958423704, 6267975073, 13064759179, 26813365624, 54226962440, 108144189873
OFFSET
1,1
COMMENTS
Row 4 of A219816
LINKS
FORMULA
Empirical: a(n) = (1/2585201673888497664000000)*n^25 - (61/620448401733239439360000)*n^24 + (41/3231502092360622080000)*n^23 - (13501/13488008733331292160000)*n^22 + (103463/2043637686868377600000)*n^21 - (102173/70067577835487232000)*n^20 + (6019/1429117263544320000)*n^19 + (26760289/16133981738434560000)*n^18 - (8215501219/107559878256230400000)*n^17 + (2269026527/1518492398911488000)*n^16 + (15379229167/3479878414172160000)*n^15 - (6289315887821/5965505852866560000)*n^14 + (1889023949230097/69597568283443200000)*n^13 - (3449492823594221/16703416388026368000)*n^12 - (4241521042837721/632705166213120000)*n^11 + (495656982597364909/1898115498639360000)*n^10 - (5695118687610620599/1222271343820800000)*n^9 + (11288184614322257833/230485453406208000)*n^8 - (77413097549306612227/327506039562240000)*n^7 - (6036501181925463108707/4257578514309120000)*n^6 + (1210248151956181009242973/32523169206528000000)*n^5 - (112323084120688445903917/325231692065280000)*n^4 + (344879943990858960613/184699479444480)*n^3 - (126899595321666973457/21202746364800)*n^2 + (33173267893330547/3346393050)*n - 5216328 for n>11
EXAMPLE
Some solutions for n=3
..1..0..0....1..0..0....1..1..1....0..0..0....0..0..0....1..0..0....0..0..0
..1..0..0....2..0..0....1..0..0....1..0..0....1..0..0....2..1..0....1..0..0
..0..0..0....2..2..0....1..0..0....2..0..0....2..1..1....2..2..1....1..0..0
..0..0..0....2..2..2....1..1..0....2..0..0....2..2..2....2..2..2....1..0..0
CROSSREFS
Sequence in context: A004638 A211033 A020479 * A264251 A140866 A219848
KEYWORD
nonn
AUTHOR
R. H. Hardin Nov 28 2012
STATUS
approved