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
Keywords
Examples
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
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)
Comments