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!)
A278016 Number of 3Xn 0..2 arrays with every element plus 1 mod 3 equal to some element at offset (-1,-1) (-1,0) (-1,1) (0,-1) (0,1) or (1,0), with upper left element zero. 1
0, 30, 410, 6372, 98410, 1516632, 23376048, 360279838, 5552721246, 85579707940, 1318971923980, 20328262601458, 313303293592114, 4828693685579504, 74420802953575212, 1146988455048830360, 17677617866311586368 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row 3 of A278014.

LINKS

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

FORMULA

Empirical: a(n) = 18*a(n-1) -32*a(n-2) -102*a(n-3) -406*a(n-4) +1452*a(n-5) +2596*a(n-6) +2458*a(n-7) -22648*a(n-8) -18454*a(n-9) +18879*a(n-10) +122984*a(n-11) -5236*a(n-12) -144156*a(n-13) -72858*a(n-14) +40286*a(n-15) +58052*a(n-16) +2232*a(n-17) -1856*a(n-18) -4224*a(n-19)

EXAMPLE

Some solutions for n=4

..0..1..0..2. .0..2..0..2. .0..1..2..0. .0..1..2..1. .0..2..1..1

..0..2..1..0. .1..0..1..2. .1..2..0..1. .0..2..0..1. .1..2..1..2

..2..0..2..2. .0..2..1..0. .2..0..1..0. .1..1..2..2. .0..1..0..0

CROSSREFS

Cf. A278014.

Sequence in context: A260913 A010835 A022722 * A282125 A296917 A255002

Adjacent sequences:  A278013 A278014 A278015 * A278017 A278018 A278019

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 08 2016

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 5 00:21 EST 2021. Contains 349530 sequences. (Running on oeis4.)