A268427 Number of distinct free polyominoes that will fit in a square of size n X n.

1, 4, 35, 1280, 263374, 205666062

Offset: 1

Author

John Mason, Feb 04 2016

Keywords

• nonn
• more

Comments

A268416 gives the number of polyominoes that fill fit inside an n X n square, but with the restriction that they have their edges aligned with the sides of the square. The current sequence removes that restriction, and hence differs from A268416 at a(5). See link "Explanation of a(5)".

Examples

			For n = 2, the four polyominoes are the 1 X 1, 1 X 2, and 2 X 2 squares or rectangles, and the 3-celled L-shape. - _N. J. A. Sloane_, Jan 21 2021
		

Links

• John Mason, Explanation of a(5)
• Talmon Silver, Computing a(6)

Crossrefs

Cf. A000105 (free polyominoes), A268416, A339848.

Extensions

A value for a(6) was submitted by Sam Vodovoz on Aug 02 2020 but this was retracted via email on Aug 03 2020. - N. J. A. Sloane, Aug 03 2020

a(5) corrected by Talmon Silver, Sep 24 2020

a(6) from Talmon Silver, Oct 01 2020

Added "free" to definition. - N. J. A. Sloane, Jan 21 2021