1,2
Andrew Clarke, Isoperimetrical Polyominoes
Andrew Clarke, Picture from Andrew Clarke's page showing the polyominoes of perimeters 4, 6, 8 and 10.
Cf. A057730.
Sequence in context: A133479 A196324 A196648 * A060515 A109723 A053594
Adjacent sequences: A057750 A057751 A057752 * A057754 A057755 A057756
nonn
N. J. A. Sloane (njas(AT)research.att.com), Nov 04 2000
Link updated by William Rex Marshall (w.r.marshall(AT)actrix.co.nz), Dec 16 2009