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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A303012 Number of nX4 0..1 arrays with every element equal to 0, 1, 2, 4 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. 1
8, 52, 187, 1047, 5299, 24030, 123538, 612923, 2935811, 14687358, 72457509, 353534815, 1751242219, 8627478474, 42358776437, 209066197468, 1029686222268, 5066170573231, 24971517088006, 122986845166051, 605538409037300 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A303016.

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) +4*a(n-2) +85*a(n-3) -321*a(n-4) -343*a(n-5) -2472*a(n-6) +7909*a(n-7) +10149*a(n-8) +29559*a(n-9) -63945*a(n-10) -98402*a(n-11) -124572*a(n-12) -16974*a(n-13) +164683*a(n-14) +221419*a(n-15) +214227*a(n-16) +32181*a(n-17) -113477*a(n-18) -158850*a(n-19) -106901*a(n-20) -44553*a(n-21) +13386*a(n-22) +51313*a(n-23) +65572*a(n-24) +39327*a(n-25) -9214*a(n-26) -54978*a(n-27) -59312*a(n-28) -20547*a(n-29) +21630*a(n-30) +31130*a(n-31) +20275*a(n-32) +1984*a(n-33) -5879*a(n-34) -5470*a(n-35) -2004*a(n-36) +570*a(n-37) +598*a(n-38) +248*a(n-39) -66*a(n-40) -32*a(n-41) -8*a(n-42) +4*a(n-43) for n>44

EXAMPLE

Some solutions for n=5

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

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

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

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

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

CROSSREFS

Cf. A303016.

Sequence in context: A199706 A302318 A035288 * A024179 A302816 A026963

Adjacent sequences:  A303009 A303010 A303011 * A303013 A303014 A303015

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 17 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 June 16 19:43 EDT 2019. Contains 324155 sequences. (Running on oeis4.)