A075219 Number of polyiamonds with n cells that tile the plane by 180-degree rotation (Conway criterion) but not by translation.

1, 0, 1, 1, 4, 4, 21, 32, 111, 200, 462, 1162, 1875, 4195, 9410, 17978, 24034, 73175, 79925, 251808, 358096, 631919, 796571, 3104082, 2980476, 6088310, 10167660, 23661369, 21477012, 84485584

Offset

1,5

References

Branko Grünbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987, Section 9.4.

Links

Table of n, a(n) for n=1..30.

Joseph Myers, Polyiamond tiling

Crossrefs

Cf. A071332, A075216, A075217, A075218, A075220, A075221, A075222, A075223, A075224, A075201, A075210.

Sequence in context: A323744 A205142 A072696 * A264650 A272450 A271892

Adjacent sequences: A075216 A075217 A075218 * A075220 A075221 A075222

Keyword

hard,nonn

Author

Joseph Myers, Sep 08 2002

Extensions

More terms from Joseph Myers, Nov 11 2003

a(29) and a(30) from Joseph Myers, Nov 21 2010

Status

approved