A302279 Number of 2 X n 0..1 arrays with every element equal to 1, 2 or 4 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

0, 3, 7, 10, 27, 45, 98, 193, 379, 778, 1523, 3085, 6138, 12281, 24603, 49106, 98363, 196557, 393234, 786481, 1572731, 3145946, 6291203, 12583117, 25165802, 50331369, 100663963, 201325602, 402654283, 805305613, 1610612610, 3221227041

Offset

1,2

Comments

Row 2 of A302278.

Links

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

Formula

Empirical: a(n) = a(n-1) + 3*a(n-2) - 4*a(n-4) for n > 5.

Example

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

Crossrefs

Cf. A302278.

Sequence in context: A302704 A235490 A041437 * A041525 A251862 A363651

Adjacent sequences: A302276 A302277 A302278 * A302280 A302281 A302282

Keyword

nonn

Author

R. H. Hardin, Apr 04 2018

Status

approved