A366001 - OEIS

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A366001

Number of free polyominoids with n cells, allowing right-angled corner-connections and flat edge-connections.

4

1, 2, 18, 243, 4881, 111697

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Table of n, a(n) for n=1..6.

Pontus von Brömssen, Illustration for sizes 1..3.

Wikipedia, Polyominoid.

Index entries for sequences related to polyominoes.

CROSSREFS

See A365995 for further details and a table of related sequences.

Cf. A366002 (fixed).

24th row of A366766.

Sequence in context: A357603 A024486 A052635 * A259270 A168562 A117514

Adjacent sequences: A365998 A365999 A366000 * A366002 A366003 A366004

KEYWORD

nonn,hard,more

AUTHOR

Pontus von Brömssen, Sep 26 2023

STATUS

approved