

A057725


Number of "polyares" of order n (turning over not allowed).


1




OFFSET

1,2


COMMENTS

An nare is a shape formed from an ncelled polyomino by removing half of each square cell in such a way that at least half of the original join between cells is retained.


REFERENCES

Enumeration attributed by Andrew Clarke to Brendan Owen.


LINKS

Table of n, a(n) for n=1..8.
Andrew Clarke, Polyares
Andrew Clarke, Picture from Andrew Clarke's page showing the 9 polyares of order 3 when turning over is allowed.
Eric Weisstein's World of Mathematics, Polyare


CROSSREFS

Cf. A057724, A000105.
Sequence in context: A255906 A260949 A049426 * A196192 A159926 A020051
Adjacent sequences: A057722 A057723 A057724 * A057726 A057727 A057728


KEYWORD

nonn,nice,more


AUTHOR

N. J. A. Sloane, Oct 29 2000


EXTENSIONS

Link updated by William Rex Marshall, Dec 16 2009


STATUS

approved



