A283106 Number of distinct envelope areas of the polyominoes of order n.

1, 1, 1, 2, 2, 4, 5, 7, 9, 11, 12, 16, 18, 22, 26, 30, 33, 37, 41, 47, 52, 58, 62, 69, 74, 80, 86, 92, 97, 106, 112, 120, 127, 135, 143, 152, 159, 168, 176, 186, 193, 205, 213, 225, 235, 246, 256, 269, 281, 291, 302

Offset

0,4

Comments

The envelope of a polyomino is the minimal rectangle containing it.

Links

Table of n, a(n) for n=0..50.

Example

a(3) = 2;
The two possible envelopes are
|*|
|*|
|*|    area = 3;
and
|*| |
|*|*|  area = 4.

Crossrefs

Cf. A071764 (distinct envelope ratios).

Sequence in context: A058678 A241410 A324753 * A030769 A030739 A211861

Adjacent sequences: A283103 A283104 A283105 * A283107 A283108 A283109

Keyword

nonn

Author

Francois Alcover, Feb 28 2017

Status

approved