A251302 Number of (n+1)X(2+1) 0..3 arrays with no 2X2 subblock having the sum of its diagonal elements less than the maximum of its antidiagonal elements

2292, 82241, 2986712, 108857571, 3969434142, 144740268503, 5277635529521, 192436288418395, 7016723335411248, 255847857685751467, 9328874242829896102, 340154872436501528124, 12402926039724152501200, 452242748130000915660845

Offset

1,1

Comments

Column 2 of A251308

Links

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

Formula

Empirical: a(n) = 64*a(n-1) -1368*a(n-2) +16182*a(n-3) -121510*a(n-4) +614295*a(n-5) -2203422*a(n-6) +5855414*a(n-7) -11858513*a(n-8) +18538655*a(n-9) -22247279*a(n-10) +19763776*a(n-11) -11486424*a(n-12) +1755813*a(n-13) +4675665*a(n-14) -6317173*a(n-15) +4895605*a(n-16) -2772914*a(n-17) +1220806*a(n-18) -416396*a(n-19) +108775*a(n-20) -22066*a(n-21) +3421*a(n-22) -352*a(n-23) +14*a(n-24)

Example

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

Crossrefs

Sequence in context: A206663 A247990 A206103 * A198146 A020404 A180454

Adjacent sequences: A251299 A251300 A251301 * A251303 A251304 A251305

Keyword

nonn

Author

R. H. Hardin, Dec 01 2014

Status

approved