A302001 Number of 4Xn 0..1 arrays with every element equal to 1, 2 or 4 horizontally or antidiagonally adjacent elements, with upper left element zero.

0, 13, 15, 74, 468, 2036, 10982, 53440, 271596, 1360466, 6832459, 34345485, 172485648, 866676017, 4353899691, 21873626234, 109891360736, 552080909728, 2773601514082, 13934283247296, 70004406947220, 351694969884786

Offset

1,2

Comments

Row 4 of A301999.

Links

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

Example

Some solutions for n=5
..0..0..1..1..0. .0..0..1..1..0. .0..0..1..1..0. .0..0..1..1..0
..0..0..0..0..0. .1..1..1..0..0. .0..0..1..0..1. .0..0..1..0..0
..1..1..0..1..1. .1..0..1..1..1. .0..1..0..1..0. .0..1..1..0..1
..1..1..1..0..0. .0..1..0..0..0. .1..0..1..0..0. .0..0..0..1..1

Crossrefs

Cf. A301999.

Sequence in context: A217252 A299593 A318543 * A109018 A237912 A268664

Adjacent sequences: A301998 A301999 A302000 * A302002 A302003 A302004

Keyword

nonn

Author

R. H. Hardin, Mar 30 2018

Status

approved