%I A144553
%S A144553 0,0,0,0,0,0,0,1,0,0,0,3,2,0,0,12,7,0,0,44,25,0,0,165,90,0,0
%N A144553 Number of polyominoes with n cells that have precisely the symmetry group 
               of order 4 generated by 90 degree rotations.
%D A144553 D. H. Redelmeier, Counting polyominoes: yet another attack, Discrete 
               Math., 36 (1981), 191-203.
%H A144553 Tomas Oliveira e Silva, <a href="http://www.ieeta.pt/~tos/animals.html">
               Enumeration of polyominoes</a>
%H A144553 D. H. Redelmeier, <a href="a056877.png">Table 3</a> of Counting polyominoes...
%Y A144553 Sequences classifying polyominoes by symmetry group: A000105, A006746, 
               A006747, A006748, A006749, A056877, A056878, A142886, A144553, A144554.
%Y A144553 Sequence in context: A160230 A059033 A133209 this_sequence A131290 A116604 
               A138741
%Y A144553 Adjacent sequences: A144550 A144551 A144552 this_sequence A144554 A144555 
               A144556
%K A144553 nonn,more
%O A144553 1,12
%A A144553 N. J. A. Sloane (njas(AT)research.att.com), Jan 01 2009