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A224193
Number of 6Xn 0..2 arrays with rows unimodal and columns nondecreasing
2
28, 784, 13524, 163746, 1519738, 11444292, 72710554, 400958714, 1960596602, 8643660124, 34817290272, 129528551708, 449030731802, 1461369918218, 4493166765659, 13121663640985, 36566337458326, 97628603745396
OFFSET
1,1
COMMENTS
Row 6 of A224190
LINKS
FORMULA
Empirical: a(n) = (1/35608838483312640000)*n^24 + (1/228261785149440000)*n^23 + (2993/8515157028618240000)*n^22 + (1189/64508765368320000)*n^21 + (112787/162193467211776000)*n^20 + (4033303/202741834014720000)*n^19 + (100023181/224083079700480000)*n^18 + (75069509/9336794987520000)*n^17 + (1246517053/10545086103552000)*n^16 + (6306246257/4393785876480000)*n^15 + (18213412351/1255367393280000)*n^14 + (38516770459/313841848320000)*n^13 + (9185104716379/10545086103552000)*n^12 + (1753572682469/337983528960000)*n^11 + (42653443424521/1647669703680000)*n^10 + (118327836601829/1098446469120000)*n^9 + (1768182454793/4763670912000)*n^8 + (698418986666497/666913927680000)*n^7 + (26428459959973901/11087444047680000)*n^6 + (31671555902461499/7391629365120000)*n^5 + (14625059352544909/2463876455040000)*n^4 + (438413487383/71292721500)*n^3 + (10755031442327/2248776129600)*n^2 + (2550558151/1338557220)*n + 1
EXAMPLE
Some solutions for n=3
..0..1..1....0..1..0....0..0..0....0..1..1....0..0..0....0..0..0....0..1..0
..1..1..1....0..1..0....1..0..0....1..1..1....0..0..0....0..1..0....0..2..0
..1..2..1....1..1..1....1..0..0....2..1..1....0..0..0....1..1..1....1..2..1
..1..2..1....1..2..2....1..1..1....2..2..1....1..2..1....2..1..1....1..2..1
..2..2..1....2..2..2....2..1..1....2..2..2....1..2..1....2..2..2....2..2..1
..2..2..1....2..2..2....2..2..2....2..2..2....1..2..2....2..2..2....2..2..1
CROSSREFS
Sequence in context: A224266 A223923 A224351 * A224010 A171302 A189901
KEYWORD
nonn
AUTHOR
R. H. Hardin Apr 01 2013
STATUS
approved