A297585 Number of 4Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1 or 4 neighboring 1s.

1, 20, 102, 254, 1017, 5263, 20771, 76340, 320326, 1353690, 5389975, 21589173, 88747475, 362176212, 1462891858, 5938102840, 24195113809, 98303450371, 398918472477, 1621218682358, 6590614515512, 26773290621678, 108760910018039

Offset

1,2

Comments

Row 4 of A297582.

Links

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

Formula

Empirical: a(n) = a(n-1) +4*a(n-2) +23*a(n-3) +59*a(n-4) -6*a(n-5) -158*a(n-6) -137*a(n-7) -2*a(n-8) +54*a(n-9) +177*a(n-10) -230*a(n-11) -89*a(n-12) +168*a(n-13) -28*a(n-14) -37*a(n-15) +4*a(n-16) +2*a(n-17)

Example

Some solutions for n=7
..0..0..0..0..0..1..1. .0..0..1..0..0..0..0. .0..0..0..0..1..1..1
..1..0..0..1..0..0..0. .0..1..0..0..0..0..1. .0..1..1..0..1..0..1
..0..1..0..1..1..1..0. .0..0..0..0..1..1..0. .0..0..0..0..1..0..1
..0..0..0..0..0..1..0. .0..0..0..0..1..0..1. .0..0..0..0..1..1..1

Crossrefs

Cf. A297582.

Sequence in context: A043217 A039394 A043997 * A113599 A077757 A126859

Adjacent sequences: A297582 A297583 A297584 * A297586 A297587 A297588

Keyword

nonn

Author

R. H. Hardin, Jan 01 2018

Status

approved