A218588 Hilltop maps: number of nX4 binary arrays indicating the locations of corresponding elements not exceeded by any horizontal or antidiagonal neighbor in a random 0..2 nX4 array

13, 225, 3565, 56629, 900213, 14309253, 227451273, 3615431533, 57468767413, 913489632033, 14520292432269, 230806004700461, 3668756125551981, 58316383606459589, 926962839870918025, 14734454596844709749

Offset

1,1

Comments

Column 4 of A218592

Links

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

Formula

Empirical: a(n) = 13*a(n-1) +40*a(n-2) +92*a(n-3) +58*a(n-4) +30*a(n-5) -72*a(n-6) +4*a(n-7) -13*a(n-8) +9*a(n-9)

Example

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

Crossrefs

Sequence in context: A237602 A050523 A160196 * A158518 A223548 A201706

Adjacent sequences: A218585 A218586 A218587 * A218589 A218590 A218591

Keyword

nonn

Author

R. H. Hardin Nov 03 2012

Status

approved