login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A323352 Number of tilings of an 8 X n rectangle using 2*n copies of the disconnected shape [oo  oo]. 5
1, 1, 1, 1, 1, 1, 5, 11, 36, 69, 112, 163, 260, 425, 897, 1845, 3910, 7524, 13683, 23675, 41741, 74882, 141758, 272059, 525251, 992342, 1841482, 3361173, 6142594, 11291891, 21037446, 39459473, 74198937, 138852912, 258417206, 478462336, 885161178, 1640011925 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,7

REFERENCES

D. E. Knuth: The Art of Computer Programming, Volume 4, Pre-fascicle 5C, Dancing Links, 2018.

LINKS

Alois P. Heinz, Table of n, a(n) for n = 0..3712

Alois P. Heinz, G.f. for A323352

D. E. Knuth, Dancing Links, 24th Annual Christmas Lecture, Stanfordonline video (2018)

D. E. Knuth, Dancing Links, arXiv:cs/0011047 [cs.DS], 2000.

Wikipedia, Dancing Links

FORMULA

G.f.: see link above.

a(n) ~ c * d^n, where d = 1.860082974490657614690253062429801614977133563402428780098509287692125963... and c = 0.175453010088369049748675582204204705345337476531410983285862441563015... - Vaclav Kotesovec, Jan 15 2019

EXAMPLE

a(6) = 5:

.

   ._._._._._._.    .___._._.___.    .___._._.___.

   | | | | | | |    |___| | |___|    |___| | |___|

   |_|_|_|_|_|_|    |___|_|_|___|    |___|_|_|___|

   | | | | | | |    |___| | |___|    | | | | | | |

   |_|_|_|_|_|_|    |___|_|_|___|    |_|_|_|_|_|_|

   | | | | | | |    |___| | |___|    |___| | |___|

   |_|_|_|_|_|_|    |___|_|_|___|    |___|_|_|___|

   | | | | | | |    |___| | |___|    | | | | | | |

   |_|_|_|_|_|_|    |___|_|_|___|    |_|_|_|_|_|_|

.

   ._._._._._._.    .___._._.___.

   | | | | | | |    |___| | |___|

   |_|_|_|_|_|_|    | | |_|_| | |

   |___| | |___|    |_|_| | |_|_|

   |___|_|_|___|    |___|_|_|___|

   | | | | | | |    |___| | |___|

   |_|_|_|_|_|_|    | | |_|_| | |

   |___| | |___|    |_|_| | |_|_|

   |___|_|_|___|    |___|_|_|___|

.

CROSSREFS

Cf. A320437, A323423, A323483, A322473.

Sequence in context: A164560 A054854 A188161 * A005178 A065315 A065317

Adjacent sequences:  A323349 A323350 A323351 * A323353 A323354 A323355

KEYWORD

nonn,easy

AUTHOR

Alois P. Heinz, Jan 12 2019

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.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 19 13:26 EDT 2019. Contains 324222 sequences. (Running on oeis4.)