This site is supported by donations to The OEIS Foundation.

 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!)
 A211102 1/4 the number of (n+1)X(n+1) 0..3 symmetric matrices with every 2X2 subblock having one or two distinct values 1
 10, 184, 6304, 416368, 54050896, 13894956304, 7116012826192, 7287811488547552, 14966388560597031328, 61754027537691698147200, 512742718215616709255295136, 8576912248102024129584312864160 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS R. H. Hardin, Table of n, a(n) for n = 1..13 EXAMPLE Some solutions for n=3 ..1..2..2..2....2..0..0..1....3..1..2..0....2..3..3..2....1..2..3..3 ..2..2..2..3....0..0..0..0....1..1..2..2....3..3..3..3....2..2..2..2 ..2..2..2..2....0..0..2..0....2..2..2..1....3..3..3..3....3..2..3..3 ..2..3..2..0....1..0..0..0....0..2..1..2....2..3..3..1....3..2..3..3 CROSSREFS Sequence in context: A304936 A239764 A179521 * A121973 A223146 A239765 Adjacent sequences:  A211099 A211100 A211101 * A211103 A211104 A211105 KEYWORD nonn AUTHOR R. H. Hardin Mar 31 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 December 13 17:17 EST 2019. Contains 329970 sequences. (Running on oeis4.)