A268795 Number of nX5 0..2 arrays with some element plus some horizontally, vertically or antidiagonally adjacent neighbor totalling two exactly once.

96, 652, 3384, 23994, 168740, 1158904, 7801688, 51781418, 339641264, 2206871084, 14226779556, 91107781858, 580148670100, 3676143046622, 23194484120032, 145793482383084, 913349363853072, 5704743147188222, 35535874740219072

Offset

1,1

Comments

Column 5 of A268798.

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. .2..2..1..2..1. .2..1..0..1..0. .0..1..0..0..0
..1..0..1..0..0. .1..2..2..2..2. .1..0..0..0..0. .0..0..0..0..1
..0..0..0..1..0. .1..2..2..2..1. .0..0..1..0..0. .0..1..0..0..1
..1..0..0..0..0. .2..1..2..2..2. .1..0..0..0..0. .0..0..1..0..0

Crossrefs

Cf. A268798.

Sequence in context: A251160 A233029 A216106 * A232405 A269032 A187610

Adjacent sequences: A268792 A268793 A268794 * A268796 A268797 A268798

Keyword

nonn

Author

R. H. Hardin, Feb 13 2016

Status

approved