A250921 Number of (n+1)X(2+1) 0..2 arrays with no 2X2 subblock having its minimum diagonal element less than its minimum antidiagonal element

344, 4148, 50722, 628146, 7811640, 97205912, 1209466635, 15047023115, 187194478151, 2328806913892, 28971725729101, 360425582996318, 4483910822941575, 55782546828291714, 693968418758619695

Offset

1,1

Comments

Column 2 of A250927

Links

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

Formula

Empirical: a(n) = 27*a(n-1) -280*a(n-2) +1630*a(n-3) -6022*a(n-4) +14885*a(n-5) -25640*a(n-6) +31686*a(n-7) -28463*a(n-8) +18548*a(n-9) -8602*a(n-10) +2711*a(n-11) -526*a(n-12) +48*a(n-13)

Example

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

Crossrefs

Sequence in context: A183674 A245994 A246630 * A262791 A186935 A340173

Adjacent sequences: A250918 A250919 A250920 * A250922 A250923 A250924

Keyword

nonn

Author

R. H. Hardin, Nov 28 2014

Status

approved