A297736 Number of 4Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 2 or 4 neighboring 1s.

1, 4, 39, 93, 362, 1103, 4795, 15646, 61063, 210279, 808250, 2870341, 10812385, 39046072, 145855473, 531944713, 1976492194, 7247306179, 26852843439, 98765306232, 365369088071, 1346120422743, 4975486687718, 18348558991141

Offset

1,2

Comments

Row 4 of A297733.

Links

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

Formula

Empirical: a(n) = 5*a(n-1) +4*a(n-2) -44*a(n-3) +47*a(n-4) -22*a(n-5) -102*a(n-6) +541*a(n-7) -336*a(n-8) -149*a(n-9) -491*a(n-10) -154*a(n-11) +1086*a(n-12) -480*a(n-13) +1243*a(n-14) -1038*a(n-15) -244*a(n-16) -259*a(n-17) +162*a(n-18) +374*a(n-19) -62*a(n-20) -44*a(n-21) -116*a(n-22) +76*a(n-23) +12*a(n-24) +24*a(n-25) -16*a(n-26) -16*a(n-27)

Example

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

Crossrefs

Cf. A297733.

Sequence in context: A016484 A278052 A093850 * A286359 A201740 A024212

Adjacent sequences: A297733 A297734 A297735 * A297737 A297738 A297739

Keyword

nonn

Author

R. H. Hardin, Jan 04 2018

Status

approved