A238318 Number of (n+1)X(3+1) 0..2 arrays with no element greater than all horizontal neighbors or less than all vertical neighbors

22, 376, 4294, 41046, 405636, 4245918, 44773061, 466364332, 4831077908, 50118953924, 520906788265, 5414918911420, 56265498867083, 584547225602293, 6073257215133643, 63102941239457036, 655660370108720902

Offset

1,1

Comments

Column 3 of A238323

Links

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

Formula

Empirical: a(n) = 14*a(n-1) -69*a(n-2) +338*a(n-3) -119*a(n-4) -205*a(n-5) +3136*a(n-6) +585*a(n-7) -35422*a(n-8) +20437*a(n-9) +61393*a(n-10) -336471*a(n-11) -66762*a(n-12) +1255786*a(n-13) -168329*a(n-14) -1982021*a(n-15) +2418579*a(n-16) +2176189*a(n-17) -8355481*a(n-18) -4601562*a(n-19) +12549690*a(n-20) +7969403*a(n-21) -9569735*a(n-22) -6645703*a(n-23) +4296381*a(n-24) +2341505*a(n-25) -1782000*a(n-26) -206421*a(n-27) +727746*a(n-28) -138501*a(n-29) -247543*a(n-30) +28937*a(n-31) +27566*a(n-32) -3059*a(n-33) +13415*a(n-34) +6590*a(n-35) -2745*a(n-36) -793*a(n-37) +610*a(n-38) +103*a(n-39) -62*a(n-40) -17*a(n-41) +a(n-42) +a(n-43)

Example

Some solutions for n=4
..2..2..0..0....2..2..2..0....2..2..2..1....2..2..2..2....1..1..0..0
..1..1..0..0....2..2..1..0....1..1..0..0....0..2..2..2....1..1..0..0
..0..1..1..1....2..2..1..1....0..0..0..0....0..1..1..0....2..2..0..0
..0..2..2..0....2..2..2..0....0..0..1..1....0..1..1..0....2..2..2..1
..2..2..2..0....2..2..2..0....1..1..1..1....0..1..1..1....2..2..2..2

Crossrefs

Sequence in context: A253878 A081127 A016196 * A167120 A167121 A167122

Adjacent sequences: A238315 A238316 A238317 * A238319 A238320 A238321

Keyword

nonn

Author

R. H. Hardin, Feb 24 2014

Status

approved