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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A300460 Number of nX3 0..1 arrays with every element equal to 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero. 1
0, 2, 2, 8, 22, 68, 212, 652, 2017, 6225, 19229, 59393, 183451, 566633, 1750167, 5405795, 16697038, 51572664, 159294072, 492016422, 1519706056, 4693962286, 14498384074, 44781599826, 138318289075, 427227905079, 1319591820767 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Column 3 of A300465.

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) +a(n-4) +8*a(n-5) +4*a(n-6) -5*a(n-7) -11*a(n-8) +6*a(n-9) -2*a(n-10) -7*a(n-11) -a(n-12) +4*a(n-13) -4*a(n-14) +a(n-15)

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A300465.

Sequence in context: A151407 A130102 A151384 * A290613 A113464 A054093

Adjacent sequences:  A300457 A300458 A300459 * A300461 A300462 A300463

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 06 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 July 8 01:25 EDT 2020. Contains 335502 sequences. (Running on oeis4.)