A268806 Number of nX5 0..2 arrays with some element plus some horizontally, vertically or antidiagonally adjacent neighbor totalling two not more than once.

144, 772, 4158, 28452, 195384, 1316226, 8734264, 57302798, 372342650, 2400532536, 15373692036, 97900054556, 620374078660, 3914367133320, 24605301916568, 154148669247610, 962830699411796, 5997782979007294, 37271323919688010

Offset

1,1

Comments

Column 5 of A268809.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +41*a(n-2) +54*a(n-3) -509*a(n-4) -2182*a(n-5) -2830*a(n-6) +1766*a(n-7) +7914*a(n-8) +2584*a(n-9) -10583*a(n-10) -6092*a(n-11) +11506*a(n-12) +5348*a(n-13) -11688*a(n-14) -620*a(n-15) +9251*a(n-16) -4462*a(n-17) -3137*a(n-18) +4774*a(n-19) -2365*a(n-20) +338*a(n-21) +198*a(n-22) -106*a(n-23) +12*a(n-24) +4*a(n-25) -a(n-26) for n>29

Example

Some solutions for n=4
..0..0..1..0..1. .0..1..0..0..0. .2..1..2..2..1. .1..0..0..1..0
..0..0..0..0..1. .0..0..0..1..0. .2..1..2..2..2. .0..0..1..0..0
..1..0..1..0..0. .0..1..0..0..0. .2..2..2..2..2. .1..0..0..0..1
..0..0..0..0..0. .1..0..0..0..0. .2..1..2..2..2. .0..0..1..0..0

Crossrefs

Cf. A268809.

Sequence in context: A033696 A233653 A233646 * A112067 A210724 A237738

Adjacent sequences: A268803 A268804 A268805 * A268807 A268808 A268809

Keyword

nonn

Author

R. H. Hardin, Feb 13 2016

Status

approved