login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A303326 Number of 4Xn 0..1 arrays with every element equal to 0, 2, 4, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. 1
8, 2, 8, 2, 12, 10, 46, 50, 204, 290, 1034, 1682, 5458, 9802, 29582, 57122, 163166, 332930, 911976, 1940450, 5149146, 11309770, 29300080, 65918162, 167721900, 384199202, 964447184, 2239277042, 5564863708, 13051463050, 32192084054 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 4 of A303325.

LINKS

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

FORMULA

Empirical: a(n) = 2*a(n-1) +9*a(n-2) -16*a(n-3) -25*a(n-4) +34*a(n-5) +15*a(n-6) +4*a(n-7) +34*a(n-8) -64*a(n-9) -42*a(n-10) +20*a(n-11) -7*a(n-12) +34*a(n-13) +21*a(n-14) -8*a(n-15) -a(n-16) -6*a(n-17) -3*a(n-18) for n>19

EXAMPLE

Some solutions for n=5

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

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

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

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

CROSSREFS

Cf. A303325.

Sequence in context: A253721 A021551 A143025 * A085967 A163960 A246849

Adjacent sequences:  A303323 A303324 A303325 * A303327 A303328 A303329

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 21 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 October 23 14:54 EDT 2019. Contains 328345 sequences. (Running on oeis4.)