This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A205304 Number of n X n 0..3 arrays with no occurrence of three equal elements in a row horizontally or vertically, and new values 0..3 introduced in row major order. 0
 1, 15, 7445, 70985206, 8615950028840, 13585407518869992739 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS EXAMPLE Some solutions for n=5 ..0..1..0..0..1....0..0..1..0..0....0..0..1..0..0....0..0..1..1..0 ..0..0..1..2..1....2..1..3..2..2....2..0..3..0..2....0..1..0..0..2 ..3..1..3..0..0....2..2..3..2..2....0..3..1..1..2....1..1..0..0..3 ..1..0..2..0..1....3..1..1..3..1....0..2..0..1..0....1..3..1..1..0 ..0..2..0..1..1....1..2..1..3..2....3..2..2..3..2....2..3..2..3..1 CROSSREFS Diagonal of A205310. Sequence in context: A205155 A208095 A271402 * A206295 A074488 A059950 Adjacent sequences:  A205301 A205302 A205303 * A205305 A205306 A205307 KEYWORD nonn AUTHOR R. H. Hardin, Jan 25 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.

Last modified June 16 19:43 EDT 2019. Contains 324155 sequences. (Running on oeis4.)