A209717 Number of nX1 0..4 arrays with every element value z a city block distance of exactly z from another element value z

1, 2, 5, 12, 33, 87, 227, 583, 1538, 4067, 10633, 27837, 72387, 188811, 493437, 1288622, 3355810, 8740288, 22783725, 59403150, 154824944, 403509362, 1051651919, 2740858097, 7144656505, 18623531350, 48542955448, 126526434447

Offset

1,2

Comments

Column 1 of A209720

Links

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

Example

Some solutions for n=7
..3....3....0....1....2....0....4....3....2....1....1....3....0....0....1....0
..4....0....0....1....4....0....4....4....2....1....1....3....0....0....1....0
..2....2....4....4....2....1....0....2....2....1....0....4....2....4....1....0
..3....3....0....1....3....1....3....3....2....1....0....3....0....0....1....2
..2....2....0....1....2....1....4....2....2....1....0....3....2....1....2....2
..4....1....0....1....4....1....4....4....2....0....0....0....1....1....0....2
..3....1....4....4....3....0....3....2....2....0....0....4....1....4....2....2

Crossrefs

Sequence in context: A176336 A010843 A084075 * A000560 A292212 A212823

Adjacent sequences: A209714 A209715 A209716 * A209718 A209719 A209720

Keyword

nonn

Author

R. H. Hardin Mar 12 2012

Status

approved