A217026 Number of city-block distance 1, pressure limit 2 movements in an nX6 array with each element moving exactly one horizontally or vertically and no element acquiring more than two neighbors

16, 70225, 103754596, 174892912804, 287247245656900, 473216230511351044, 778956312256094880625, 1282337355733724881761856, 2110951958198074542626828769, 3475005538598697157658237172049

Offset

1,1

Comments

Column 6 of A217028

Links

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

Example

Some solutions for n=2 (movement: 0=n 1=e 2=s 3=w)
..2..3..2..3..1..3....1..2..2..3..3..3....2..2..1..3..3..2....2..3..2..2..2..3
..0..1..1..1..1..0....0..0..3..3..0..3....0..3..0..1..1..3....0..0..0..1..0..0

Crossrefs

Sequence in context: A105312 A013758 A078186 * A087926 A193135 A368326

Adjacent sequences: A217023 A217024 A217025 * A217027 A217028 A217029

Keyword

nonn

Author

R. H. Hardin Sep 24 2012

Status

approved