A296595 Number of nX4 0..1 arrays with each 1 horizontally, vertically or antidiagonally adjacent to 1, 2 or 3 neighboring 1s.

7, 136, 1441, 16524, 194743, 2271055, 26487173, 309059200, 3606151826, 42075891572, 490933874225, 5728147443412, 66835159508794, 779822462956391, 9098850687932878, 106164013544171785, 1238705647362376924

Offset

1,1

Comments

Column 4 of A296599.

Links

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

Formula

Empirical: a(n) = 8*a(n-1) +26*a(n-2) +168*a(n-3) +247*a(n-4) +901*a(n-5) +146*a(n-6) +2230*a(n-7) -5046*a(n-8) -13683*a(n-9) +34114*a(n-10) -28566*a(n-11) -101067*a(n-12) +178744*a(n-13) +58416*a(n-14) -360931*a(n-15) +145098*a(n-16) +371598*a(n-17) -252966*a(n-18) -191251*a(n-19) +198012*a(n-20) +122010*a(n-21) -53967*a(n-22) -82652*a(n-23) -15645*a(n-24) +19759*a(n-25) +23703*a(n-26) +15676*a(n-27) -3224*a(n-28) -7147*a(n-29) +250*a(n-30) +849*a(n-31) -3219*a(n-32) +897*a(n-33) -231*a(n-34) +514*a(n-35) +640*a(n-36) +24*a(n-37) +6*a(n-38) -92*a(n-39) -92*a(n-40) -67*a(n-41) -38*a(n-42) -15*a(n-43) -4*a(n-44)

Example

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

Crossrefs

Cf. A296599.

Sequence in context: A183478 A292395 A081793 * A368630 A210028 A243684

Adjacent sequences: A296592 A296593 A296594 * A296596 A296597 A296598

Keyword

nonn

Author

R. H. Hardin, Dec 16 2017

Status

approved