A302208 Number of nX4 0..1 arrays with every element equal to 0, 2 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

1, 13, 5, 7, 18, 55, 172, 575, 1962, 6756, 23400, 81288, 283089, 987275, 3444621, 12023434, 41982749, 146612525, 512036344, 1788383898, 6246509941, 21818284060, 76209472929, 266195826556, 929812279542, 3247807389634, 11344517688838

Offset

1,2

Comments

Column 4 of A302212.

Links

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

Formula

Empirical: a(n) = 4*a(n-1) -3*a(n-2) +12*a(n-3) -21*a(n-4) -18*a(n-5) -16*a(n-6) +14*a(n-7) +21*a(n-8) +37*a(n-9) -6*a(n-10) +25*a(n-11) +62*a(n-12) -20*a(n-13) -7*a(n-14) -75*a(n-15) -76*a(n-16) -51*a(n-17) +57*a(n-18) +43*a(n-19) +35*a(n-20) +30*a(n-21) -35*a(n-22) -27*a(n-23) +10*a(n-24) +2*a(n-25) +6*a(n-26) -2*a(n-28) for n>32

Example

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

Crossrefs

Cf. A302212.

Sequence in context: A248146 A097484 A098326 * A068662 A235366 A166207

Adjacent sequences: A302205 A302206 A302207 * A302209 A302210 A302211

Keyword

nonn

Author

R. H. Hardin, Apr 03 2018

Status

approved