A297982 Number of n X 4 0..1 arrays with every element equal to 0, 2, 3 or 6 king-move adjacent elements, with upper left element zero.

1, 17, 5, 15, 23, 43, 79, 184, 380, 830, 1776, 3815, 8227, 17737, 38335, 82673, 178600, 385419, 832806, 1798455, 3885410, 8392102, 18129621, 39164405, 84609476, 182786176, 394886142, 853110431, 1843063212, 3981796702, 8602359868

Offset

1,2

Comments

Column 4 of A297986.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +2*a(n-2) -3*a(n-3) +2*a(n-4) -3*a(n-5) -9*a(n-6) -3*a(n-7) -3*a(n-8) +17*a(n-9) +13*a(n-10) +11*a(n-11) -5*a(n-12) -14*a(n-13) -a(n-14) +7*a(n-15) +10*a(n-16) -8*a(n-17) -12*a(n-18) -3*a(n-19) -5*a(n-20) +3*a(n-21) +2*a(n-22) for n>28.

Example

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

Crossrefs

Cf. A297986.

Sequence in context: A196924 A109215 A254070 * A298631 A338559 A243933

Adjacent sequences: A297979 A297980 A297981 * A297983 A297984 A297985

Keyword

nonn

Author

R. H. Hardin, Jan 10 2018

Status

approved