A297683 - OEIS

A297683

Number of 3Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 0, 1 or 4 neighboring 1s.

8, 33, 150, 629, 2790, 12110, 52889, 230406, 1005170, 4382278, 19110183, 83327912, 363357551, 1584416863, 6908888883, 30126285845, 131366174343, 572824066436, 2497808102429, 10891729292407, 47493549245614, 207096331298600

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Row 3 of A297682.

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +7*a(n-2) +11*a(n-3) +17*a(n-4) -7*a(n-5) -10*a(n-6) -18*a(n-7) -a(n-8)

EXAMPLE

Some solutions for n=7

..0..1..0..0..0..0..1. .0..0..0..1..0..0..0. .0..0..1..0..0..0..1

..1..0..0..0..0..1..1. .0..0..0..1..0..0..0. .1..0..0..0..0..0..0

..0..0..0..0..1..0..1. .0..0..0..0..1..0..1. .1..0..1..1..0..0..1

CROSSREFS

Cf. A297682.

Sequence in context: A212404 A048877 A349101 * A346819 A220590 A001407

Adjacent sequences: A297680 A297681 A297682 * A297684 A297685 A297686

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 03 2018

STATUS

approved