login
A300883
Number of nX3 0..1 arrays with every element equal to 0, 1, 3, 4 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.
1
3, 2, 4, 8, 17, 57, 148, 356, 864, 2272, 5766, 14438, 36379, 92632, 234473, 592300, 1497878, 3794198, 9602820, 24292985, 61469034, 155580439, 393724501, 996303601, 2521217660, 6380413994, 16146453573, 40860032492, 103400766211, 261668897174
OFFSET
1,1
COMMENTS
Column 3 of A300888.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-2) +7*a(n-3) +6*a(n-4) -15*a(n-5) -47*a(n-6) -47*a(n-7) +5*a(n-8) +102*a(n-9) +86*a(n-10) +23*a(n-12) +28*a(n-13) -51*a(n-14) -119*a(n-15) -24*a(n-16) +111*a(n-17) +69*a(n-18) -21*a(n-19) -27*a(n-20) -6*a(n-21) for n>25
EXAMPLE
Some solutions for n=5
..0..1..0. .0..0..0. .0..0..0. .0..0..0. .0..1..1. .0..0..1. .0..1..1
..0..0..1. .1..0..0. .1..0..0. .1..0..0. .1..1..1. .1..1..0. .1..1..1
..0..0..1. .0..1..0. .0..0..1. .1..0..1. .1..0..1. .0..1..0. .1..0..1
..1..0..0. .1..0..0. .0..0..1. .0..0..1. .1..1..1. .0..0..0. .1..0..0
..0..1..1. .0..1..0. .0..0..0. .0..0..0. .1..1..0. .0..0..1. .0..1..1
CROSSREFS
Cf. A300888.
Sequence in context: A075087 A084657 A171559 * A019916 A201838 A099257
KEYWORD
nonn
AUTHOR
R. H. Hardin, Mar 14 2018
STATUS
approved