login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A302872 Number of nX3 0..1 arrays with every element equal to 0, 1, 3, 4 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. 1
3, 11, 17, 37, 82, 209, 536, 1549, 4513, 13980, 44424, 142457, 463592, 1518144, 4985864, 16423493, 54170895, 178797985, 590488247, 1950654770, 6444889749, 21296082916, 70373480203, 232558689443, 768538881502, 2539828012418 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A302877.

LINKS

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

FORMULA

Empirical: a(n) = 3*a(n-1) +9*a(n-3) -15*a(n-4) -5*a(n-5) -22*a(n-6) -7*a(n-7) +9*a(n-8) -32*a(n-9) -10*a(n-10) -16*a(n-11) -40*a(n-12) -16*a(n-13) for n>16

EXAMPLE

Some solutions for n=5

..0..0..1. .0..0..1. .0..0..1. .0..0..1. .0..1..0. .0..0..1. .0..0..0

..0..1..0. .1..1..1. .0..1..0. .1..1..1. .0..1..0. .1..1..1. .0..1..0

..0..1..0. .1..0..1. .0..1..0. .1..0..1. .0..1..0. .1..0..1. .0..1..0

..0..1..0. .1..0..0. .1..1..0. .1..0..1. .0..0..0. .1..0..1. .0..1..0

..0..0..0. .1..0..1. .0..1..0. .0..1..1. .0..1..1. .1..1..0. .0..1..0

CROSSREFS

Cf. A302877.

Sequence in context: A197225 A181507 A154934 * A023865 A024592 A203162

Adjacent sequences:  A302869 A302870 A302871 * A302873 A302874 A302875

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 15 2018

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 9 04:45 EST 2021. Contains 349626 sequences. (Running on oeis4.)