This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A186463 Number of (n+1)X(n+1) 0..2 arrays with every 2X2 subblock commuting with each of its horizontal and vertical 2X2 subblock neighbors 1
 81, 129, 942, 3186, 13278, 34314, 136086, 399018, 1537038, 4607034, 16888062, 51777498, 185254926, 580089834, 2037893214, 6478793466, 22450788942, 72203998026, 247694103486, 803564559834, 2735884703406, 8933648141802 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Diagonal of A186472 LINKS R. H. Hardin, Table of n, a(n) for n = 1..23 EXAMPLE Some solutions for 3X3 ..0..0..2....1..0..0....0..0..1....0..2..0....1..1..0....1..2..0....0..0..0 ..0..0..2....2..0..0....0..0..1....2..0..2....2..0..1....0..0..2....2..0..0 ..0..0..2....0..2..1....0..0..1....0..2..2....0..2..2....0..0..1....0..2..1 CROSSREFS Sequence in context: A053887 A119943 A001245 * A046317 A046374 A153259 Adjacent sequences:  A186460 A186461 A186462 * A186464 A186465 A186466 KEYWORD nonn AUTHOR R. H. Hardin Feb 22 2011 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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.