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!)
A207393 Number of 4Xn 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 0 1 and 1 1 0 vertically 1
8, 64, 200, 643, 2356, 7561, 23071, 72410, 223804, 678174, 2060069, 6253794, 18886989, 56994221, 172026022, 518680170, 1563104966, 4710798095, 14194683842, 42764679095, 128836561789, 388135277342, 1169254115920, 3522329560926 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 4 of A207391

LINKS

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

FORMULA

Empirical: a(n) = 5*a(n-1) -8*a(n-2) +19*a(n-3) -54*a(n-4) +51*a(n-5) -64*a(n-6) +169*a(n-7) -78*a(n-8) +62*a(n-9) -265*a(n-10) +27*a(n-11) -41*a(n-12) +277*a(n-13) +16*a(n-14) +40*a(n-15) -162*a(n-16) -31*a(n-17) -10*a(n-18) +41*a(n-19) +13*a(n-20) -6*a(n-22)

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A207455 A207307 A207113 * A207940 A016743 A340695

Adjacent sequences:  A207390 A207391 A207392 * A207394 A207395 A207396

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 17 2012

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 April 17 02:25 EDT 2021. Contains 343059 sequences. (Running on oeis4.)