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!)
A208373 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 0 1 0 vertically 1
31, 961, 11067, 177909, 2563359, 38542393, 570085195, 8487780687, 126039261499, 1873614472027, 27839846618695, 413742327695195, 6148396146149603, 91370604275750753, 1357831649082497201, 20178435819755002559 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Row 7 of A208369
LINKS
FORMULA
Empirical: a(n) = 178*a(n-2) +932*a(n-3) -2956*a(n-4) -23754*a(n-5) +20253*a(n-6) +256486*a(n-7) -113835*a(n-8) -1502278*a(n-9) +783938*a(n-10) +4923968*a(n-11) -3657059*a(n-12) -8430388*a(n-13) +8233841*a(n-14) +6798200*a(n-15) -8443642*a(n-16) -2506050*a(n-17) +4235409*a(n-18) +420518*a(n-19) -1084169*a(n-20) -45082*a(n-21) +134907*a(n-22) +7426*a(n-23) -6196*a(n-24) -610*a(n-25)
EXAMPLE
Some solutions for n=4
..0..1..1..0....0..1..1..1....0..1..1..1....1..0..1..0....0..1..0..1
..1..1..0..0....1..0..1..1....1..0..1..1....1..1..0..1....0..1..0..0
..1..0..1..0....1..0..1..0....1..1..0..0....1..1..1..1....0..1..0..0
..0..1..1..0....1..0..1..0....1..1..0..1....0..1..1..1....0..1..0..0
..1..1..1..0....1..0..1..0....1..1..0..1....1..1..0..0....0..1..0..0
..1..0..1..0....1..0..1..0....1..1..0..0....1..0..1..0....0..1..0..0
..1..1..0..0....1..0..1..0....1..1..0..0....1..0..1..0....0..1..0..0
CROSSREFS
Sequence in context: A208168 A207441 A207431 * A171305 A009975 A042862
KEYWORD
nonn
AUTHOR
R. H. Hardin Feb 25 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 | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 20 16:26 EDT 2024. Contains 373528 sequences. (Running on oeis4.)