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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A209221 Number of nX5 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 0 and 1 1 1 vertically 1
15, 225, 240, 504, 900, 1776, 3456, 6300, 12656, 24124, 45276, 88400, 170280, 323760, 618496, 1202400, 2300200, 4360824, 8464860, 16284576, 30897024, 59537156, 115023968, 219164204, 419459908, 811024296, 1553149080, 2962595040 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A209224

LINKS

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

FORMULA

Empirical: a(n) = 9*a(n-3) +2*a(n-4) -33*a(n-6) +10*a(n-7) +3*a(n-8) +66*a(n-9) -33*a(n-10) +5*a(n-11) -83*a(n-12) +39*a(n-13) -20*a(n-14) +78*a(n-15) +3*a(n-16) -7*a(n-17) -45*a(n-18) -30*a(n-19) +8*a(n-20) +22*a(n-21) +10*a(n-22) +2*a(n-23) -6*a(n-24) +a(n-25) +a(n-27) for n>29

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A297669 A171320 A078364 * A207690 A207925 A208105

Adjacent sequences:  A209218 A209219 A209220 * A209222 A209223 A209224

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 06 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 November 19 11:09 EST 2019. Contains 329319 sequences. (Running on oeis4.)