The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A175564 Number of n X n binary matrices that contain no 2 X 2 submatrix consisting of all zeros or all ones. 1
 1, 2, 14, 156, 840, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS FORMULA For n >= 5, a(n) = 0. CROSSREFS Cf. A175563. Sequence in context: A301931 A060193 A222200 * A332693 A196791 A349312 Adjacent sequences:  A175561 A175562 A175563 * A175565 A175566 A175567 KEYWORD easy,nonn AUTHOR Max Alekseyev, Jul 03 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 | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified May 19 17:07 EDT 2022. Contains 353847 sequences. (Running on oeis4.)