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 1-3 of 3 results.

A270061 Number A(n,k) of tilings of a k X n rectangle using monominoes and trominoes of any shape; square array A(n,k), n>=0, k>=0, read by antidiagonals.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 5, 2, 1, 1, 3, 14, 14, 3, 1, 1, 4, 45, 93, 45, 4, 1, 1, 6, 140, 590, 590, 140, 6, 1, 1, 9, 438, 3710, 7517, 3710, 438, 9, 1, 1, 13, 1371, 23509, 96176, 96176, 23509, 1371, 13, 1, 1, 19, 4287, 148796, 1238818, 2501946, 1238818, 148796, 4287, 19, 1
Offset: 0

Views

Author

Alois P. Heinz, Mar 09 2016

Keywords

Examples

			A(2,3) = A(3,2) = 14:
  ._____.  ._____.  ._____.  ._____.  ._____.  ._____.  ._____.
  |_____|  |_|_|_|  |_____|  |_| |_|  | |_|_|  | ._|_|  |_. |_|
  |_____|  |_____|  |_|_|_|  |___|_|  |___|_|  |_|_|_|  |_|_|_|
.
  ._____.  ._____.  ._____.  ._____.  ._____.  ._____.  ._____.
  |_|_|_|  | ._| |  | |_. |  |_|_| |  |_| |_|  |_| ._|  |_|_. |
  |_|_|_|  |_|___|  |___|_|  |_|___|  |_|___|  |_|_|_|  |_|_|_|  .
.
Square array A(n,k) begins:
  1, 1,   1,     1,       1,        1,          1, ...
  1, 1,   1,     2,       3,        4,          6, ...
  1, 1,   5,    14,      45,      140,        438, ...
  1, 2,  14,    93,     590,     3710,      23509, ...
  1, 3,  45,   590,    7517,    96176,    1238818, ...
  1, 4, 140,  3710,   96176,  2501946,   65410388, ...
  1, 6, 438, 23509, 1238818, 65410388, 3473827027, ...
		

Crossrefs

Columns (or rows) k=0-10 give: A000012, A000930, A270062, A270063, A270064, A270065, A270066, A270067, A270068, A270069, A270070.
Main diagonal gives A270071.
Cf. A233320.

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).

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 1-3 of 3 results.