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

 

Logo

Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing.
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A181273 Number of n X n binary matrices M with rows in strictly increasing order and rows of M*Mtranspose (mod 2) in strictly decreasing order 0
2, 3, 9, 58, 1991, 177193, 50841045, 40797077296 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Diagonal of A181274

LINKS

Table of n, a(n) for n=1..8.

EXAMPLE

M and M*Mtranspose (mod 2) for 4X4

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

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

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

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

CROSSREFS

Sequence in context: A037389 A037425 A226967 * A270394 A120032 A126884

Adjacent sequences:  A181270 A181271 A181272 * A181274 A181275 A181276

KEYWORD

nonn

AUTHOR

R. H. Hardin Oct 10 2010

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 December 12 09:36 EST 2019. Contains 329953 sequences. (Running on oeis4.)