A224312 Number of 4Xn 0..2 arrays with diagonals and rows unimodal and antidiagonals nondecreasing

81, 1944, 11361, 45453, 164514, 562760, 1825800, 5585818, 16074063, 43567313, 111632420, 271667665, 630966702, 1405080075, 3012670262, 6242914246, 12544093805, 24510622826, 46689053477, 86888070112, 158272032306

Offset

1,1

Comments

Row 4 of A224310

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = (1/106748928000)*n^16 + (1/13343616000)*n^15 + (89/9340531200)*n^14 + (5179/37362124800)*n^13 + (126779/28740096000)*n^12 + (103081/1306368000)*n^11 + (18019/13063680)*n^10 - (76841/261273600)*n^9 + (81547771/746496000)*n^8 + (262193969/1306368000)*n^7 - (318727393/1437004800)*n^6 + (10868710291/359251200)*n^5 - (1656836125459/15567552000)*n^4 + (975909282919/1297296000)*n^3 - (26075217263/10810800)*n^2 + (77958821/8190)*n - 17954 for n>6

Example

Some solutions for n=3
..0..1..0....1..0..0....2..2..2....0..1..0....0..1..0....2..1..1....1..1..1
..1..2..1....1..2..1....2..2..0....2..0..0....1..2..1....1..1..2....1..1..0
..2..2..2....2..1..1....2..1..0....0..0..0....2..1..0....1..2..0....2..1..1
..2..2..1....2..2..1....1..1..1....2..0..0....1..1..2....2..0..0....1..2..1

Crossrefs

Sequence in context: A296650 A233371 A225019 * A224376 A237957 A238038

Adjacent sequences: A224309 A224310 A224311 * A224313 A224314 A224315

Keyword

nonn

Author

R. H. Hardin Apr 03 2013

Status

approved