login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A206571 Number of nX2 0..3 arrays avoiding the pattern z-1 z-1 z in any row, column or nw-to-se diagonal 4
16, 256, 3721, 53824, 777924, 11242609, 162486009, 2348371600, 33940324441, 490529342884, 7089470711236, 102461949277801, 1480851163185241, 21402288176353681, 309320714104227225, 4470517516089946896 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A206577

LINKS

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

FORMULA

Empirical: a(n) = 16*a(n-1) -12*a(n-2) -166*a(n-3) +134*a(n-4) +1595*a(n-5) -1291*a(n-6) -11538*a(n-7) +9401*a(n-8) +344*a(n-9) -2098*a(n-10) +2832*a(n-11) -1207*a(n-12) -846*a(n-13) +548*a(n-14) +637*a(n-15) -488*a(n-16) +102*a(n-17) -13*a(n-18) -161*a(n-19) +85*a(n-20) +20*a(n-21) -14*a(n-22) -4*a(n-23) +6*a(n-24) -4*a(n-25) +a(n-26) +2*a(n-27) -a(n-28)

EXAMPLE

Some solutions for n=4

..2..2....1..3....1..0....2..0....0..0....0..2....3..1....2..3....3..3....1..0

..1..0....0..1....2..3....1..0....3..0....1..1....1..2....3..0....0..1....1..3

..0..3....0..0....2..1....2..0....1..2....3..1....0..1....1..2....0..0....1..3

..0..0....2..0....1..0....1..2....2..0....0..0....0..0....3..2....3..2....3..1

CROSSREFS

Sequence in context: A294329 A267929 A122609 * A206791 A221665 A227592

Adjacent sequences:  A206568 A206569 A206570 * A206572 A206573 A206574

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 09 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 29 21:32 EST 2021. Contains 349416 sequences. (Running on oeis4.)