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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A227640 Number of nX5 0,1 arrays indicating 2X2 subblocks of some larger (n+1)X6 binary array having determinant equal to one, with rows and columns of the latter in nondecreasing lexicographic order 1
5, 44, 377, 3202, 25241, 179234, 1147095, 6679750, 35730988, 177168580, 820755334, 3576675995, 14747597428, 57825369396, 216544923909, 777378404391, 2683990390975, 8937664937815, 28776814807337, 89782546245762 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A227641

LINKS

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

R. H. Hardin, Empirical polynomial of degree 39

FORMULA

Empirical polynomial of degree 39 (see link above)

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A068311 A109984 A247776 * A096355 A222508 A220841

Adjacent sequences:  A227637 A227638 A227639 * A227641 A227642 A227643

KEYWORD

nonn

AUTHOR

R. H. Hardin Jul 18 2013

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 August 20 10:17 EDT 2019. Contains 326149 sequences. (Running on oeis4.)