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

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A216598 Number of distinct connected planar figures that can be formed from n 1 X 2 rectangles (or dominoes). 6
 1, 2, 16, 164, 1866, 22518, 282184, 3630256, 47614214, 633835642, 8537220172 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS "Connected" means "connected by edges". Rotations and reflections are considered different (cf. A056786). Internal arrangement of dominoes is significant (cf. A056785). - Aaron N. Siegel, May 22 2022 LINKS Table of n, a(n) for n=0..10. Manfred Scheucher, Sage Script N. J. A. Sloane, Illustration of initial terms of A056786, A216598, A216583, A216595, A216492, A216581 N. J. A. Sloane, Illustration of third term of A056786, A216598, A216583, A216595, A216492, A216581 (a better drawing for the third term) M. Vicher, Polyforms Index entries for sequences related to dominoes CROSSREFS Cf. A056786, A216598, A216583, A216595, A216492, A216581. Sequence in context: A011552 A326362 A287222 * A219397 A275912 A337870 Adjacent sequences: A216595 A216596 A216597 * A216599 A216600 A216601 KEYWORD nonn,more,nice,hard AUTHOR N. J. A. Sloane, Sep 09 2012 EXTENSIONS a(4) found via equivalence class decomposition over bounding boxes by the Forest Grove Community School Math Club - Markus J. Q. Roberts, Apr 03 2013 a(5)-a(9) from Manfred Scheucher, Jun 06 2015 a(10) from Aaron N. Siegel, May 22 2022 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 28 18:29 EDT 2023. Contains 363019 sequences. (Running on oeis4.)