login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A297509 Number of 4Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1 or 2 neighboring 1s. 1
1, 87, 531, 2281, 23348, 191192, 1247716, 9450219, 74086027, 542295341, 4014135733, 30366147431, 226985241429, 1690164545942, 12658565659102, 94748613114792, 707806468257951, 5292426347783239, 39588593164337549 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Row 4 of A297506.

LINKS

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

FORMULA

Empirical: a(n) = 6*a(n-1) +a(n-2) +122*a(n-3) -209*a(n-4) -1087*a(n-5) -354*a(n-6) +4059*a(n-7) +1206*a(n-8) +3818*a(n-9) +692*a(n-10) -11767*a(n-11) -6075*a(n-12) -2835*a(n-13) -949*a(n-14) +8451*a(n-15) +6295*a(n-16) -636*a(n-17) +2500*a(n-18) -3242*a(n-19) -1428*a(n-20) +742*a(n-21) +74*a(n-22) -24*a(n-23) +2*a(n-24)

EXAMPLE

Some solutions for n=6

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

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

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

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

CROSSREFS

Cf. A297506.

Sequence in context: A221312 A098139 A359341 * A259510 A109601 A297723

Adjacent sequences: A297506 A297507 A297508 * A297510 A297511 A297512

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 31 2017

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified February 2 11:35 EST 2023. Contains 360011 sequences. (Running on oeis4.)