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!)
A266501 Number of n X n (0,1)-matrices such that there is a row and a column with equal sums. 1
1, 2, 12, 500, 63828, 33394572, 68548156212, 562584834624864 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
The ratio a(n)/2^(n^2) tends to 1 as n grows.
LINKS
FORMULA
a(n) = 2^(n^2) - A266500(n).
CROSSREFS
Sequence in context: A013173 A013147 A250110 * A264952 A324790 A050643
KEYWORD
nonn,hard,more
AUTHOR
Max Alekseyev, Dec 30 2015
EXTENSIONS
a(6)-a(7) from Hiroaki Yamanouchi, Dec 31 2015
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 February 25 16:38 EST 2024. Contains 370332 sequences. (Running on oeis4.)