cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-7 of 7 results.

A219994 Number of tilings of an n X n square using dominoes and right trominoes.

Original entry on oeis.org

1, 0, 2, 8, 380, 21272, 5350806, 3238675344, 6652506271144, 38896105985522272, 711716770252031164458, 38776997923112110535353528, 6460929292946758939597712150496, 3245656750963660788826395580466708824, 4953412325525289651086730443567098343730966, 22873302288206466754758793232467436030071524731072
Offset: 0

Views

Author

Alois P. Heinz, Dec 02 2012

Keywords

Examples

			a(3) = 8, because there are 8 tilings of a 3 X 3 square using dominoes and right trominoes:
  .___._.   .___._.   .___._.   .___._.
  |___| |   |___| |   |___| |   |_. | |
  | ._|_|   | | |_|   | |___|   | |_|_|
  |_|___|   |_|___|   |_|___|   |_|___|
  ._.___.   ._.___.   ._.___.   ._.___.
  | |___|   | | ._|   | |___|   | |___|
  |___| |   |_|_| |   |_|_. |   |_| | |
  |___|_|   |___|_|   |___|_|   |___|_|  .
		

Crossrefs

Main diagonal of A219987.

A219874 Number of tilings of an n X n square using dominoes and straight (3 X 1) trominoes.

Original entry on oeis.org

1, 0, 2, 14, 184, 9612, 1143834, 354859954, 295743829064, 631206895803116, 3541054185616706122, 51821077154605344550820, 1976225122734369352127065686, 196913655491597719598898811003348, 51179690353659852099434654264900753288, 34716223657627061096793572212632925410608268
Offset: 0

Views

Author

Alois P. Heinz, Nov 30 2012

Keywords

Examples

			a(3) = 14, because there are 14 tilings of a 3 X 3 square using dominoes and straight (3 X 1) trominoes:
  ._____. ._____. ._____. ._____. .___._. .___._. .___._.
  | | | | | | | | | |___| | |___| | | | | |___| | |___| |
  | | | | | |_|_| | |___| | | | | |_|_| | |___| | | | | |
  |_|_|_| |_|___| |_|___| |_|_|_| |___|_| |___|_| |_|_|_|
  ._____. ._____. ._____. ._____. ._____. ._____. ._____.
  |_____| |_____| |_____| |_____| | |___| | | | | |___| |
  |_____| | |___| | | | | |___| | |_|___| |_|_|_| |___|_|
  |_____| |_|___| |_|_|_| |___|_| |_____| |_____| |_____|  .
		

Crossrefs

Main diagonal of A219866.

Extensions

a(12) from Alois P. Heinz, Sep 30 2014
a(13)-a(15) (using Liang Kai's terms in A219866) from Alois P. Heinz, Mar 12 2025

A220061 Number of tilings of an n X n square using right trominoes and 1 X 1 tiles.

Original entry on oeis.org

1, 1, 5, 39, 2023, 249651, 128938297, 207866584389, 1208344842789831, 23649239068131551559, 1609120545126107661426575, 375082120094104660413783094451, 301522432794951154854984388046484015, 833441700776362178606942848178200903068675, 7931715551857283775957120938092133944383839378911
Offset: 0

Views

Author

Alois P. Heinz, Dec 03 2012

Keywords

Examples

			a(2) = 5, because there are 5 tilings of a 2 X 2 square using right trominoes and 1 X 1 tiles:
  ._._.   ._._.   .___.   .___.   ._._.
  |_|_|   | |_|   | ._|   |_. |   |_| |
  |_|_|   |___|   |_|_|   |_|_|   |___|
		

Crossrefs

Main diagonal of A220054.
Cf. A233807.

A219952 Number of tilings of an n X n square using right trominoes and 2 X 2 tiles.

Original entry on oeis.org

1, 0, 1, 0, 6, 0, 545, 5504, 652036, 44013568, 11112714624, 3517475475328, 2781543486427548, 3568483481372543360, 9829161878198755474915, 48599777948701165162242560, 484370819140388708451108625276, 9036085159101926537420075859958528
Offset: 0

Views

Author

Alois P. Heinz, Dec 01 2012

Keywords

Examples

			a(4) = 6, because there are 6 tilings of a 4 X 4 square using right trominoes and 2 X 2 tiles:
  .___.___. .___.___. .___.___. .___.___. .___.___. .___.___.
  | . | . | | ._|_. | | ._| . | | ._|_. | | ._|_. | | . |_. |
  |___|___| |_| . |_| |_| |___| |_| ._|_| |_|_. |_| |___| |_|
  | . | . | | |___| | | |___| | | |_| . | | . |_| | | |___| |
  |___|___| |___|___| |___|___| |___|___| |___|___| |___|___|
		

Crossrefs

Main diagonal of A219946.
Cf. A233807.

Extensions

a(15)-a(16) from Alois P. Heinz, Sep 24 2014
a(17) from Alois P. Heinz, Nov 18 2018

A353777 Number of tilings of an n X n square using dominoes, monominoes and 2 X 2 tiles.

Original entry on oeis.org

1, 1, 8, 163, 15623, 5684228, 8459468955, 50280716999785, 1202536689448371122, 115462301811597894998929, 44537596159273736617786474211, 69003082378039459280864860681919942, 429429579883061866326542598342441907826951, 10734684843612889640707750537898705644071715970757
Offset: 0

Views

Author

Alois P. Heinz, May 07 2022

Keywords

Examples

			a(2) = 8:
  .___.  .___.  .___.  .___.  .___.  .___.  .___.  .___.
  |   |  |_|_|  |___|  | | |  |_|_|  |___|  |_| |  | |_|
  |___|  |_|_|  |___|  |_|_|  |___|  |_|_|  |_|_|  |_|_| .
		

Crossrefs

Formula

a(n) = A352589(n,n).

A219975 Number of tilings of an n X n square using straight (3 X 1) trominoes and 2 X 2 tiles.

Original entry on oeis.org

1, 0, 1, 2, 3, 28, 267, 2744, 66653, 2766100, 141365332, 13305552648, 2149055591278, 493880634209398, 192321197859269019, 124351154502319720238, 122893248485909264026734, 199405053536180281080458422, 527809383857797224536981601752
Offset: 0

Views

Author

Alois P. Heinz, Dec 02 2012

Keywords

Examples

			a(4) = 3, because there are 3 tilings of a 4 X 4 square using straight (3 X 1) trominoes and 2 X 2 tiles:
  ._._____.  ._____._.  ._._._._.
  | |_____|  |_____| |  | . | . |
  | | . | |  | | . | |  |___|___|
  |_|___| |  | |___|_|  | . | . |
  |_____|_|  |_|_____|  |___|___|  .
		

Crossrefs

Main diagonal of A219967.
Cf. A233807.

Extensions

a(12) from Alois P. Heinz, Sep 24 2014
a(13)-a(18) from Martin Fuller, Apr 09 2025

A353934 Number of tilings of an n X n square using right trominoes, dominoes, and monominoes.

Original entry on oeis.org

1, 1, 11, 369, 83374, 90916452, 546063639624, 17259079054003609, 2916019543694306398589, 2620143594924539083433405392, 12541344781693990981151732534871036, 319608708168951734031266758322647453517098, 43373075269161087186367095378869660507262626652634
Offset: 0

Views

Author

Alois P. Heinz, May 11 2022

Keywords

Examples

			a(2) = 11:
  .___. .___. .___. .___. .___. .___. .___. .___. .___. .___. .___.
  |_|_| |___| | | | |_|_| |___| |_| | | |_| |_| | |_. | | ._| | |_|
  |_|_| |___| |_|_| |___| |_|_| |_|_| |_|_| |___| |_|_| |_|_| |___| .
		

Crossrefs

Formula

a(n) = A353877(n,n).
Showing 1-7 of 7 results.