%I A000988 M1749 N0693
%S A000988 1,1,2,7,18,60,196,704,2500,9189,33896,126759,476270,1802312,
%T A000988 6849777,26152418,100203194,385221143,1485200848,5741256764,
%U A000988 22245940545,86383382827,336093325058,1309998125640
%N A000988 Number of one-sided polyominoes with n cells.
%C A000988 A000105(n) + A030228(n) = a(n) because the number of free polyominoes 
               plus the number of polyominoes lacking bilateral symmetry equals 
               the number of one-sided polyominoes. - Graeme McRae" (g_m(AT)mcraefamily.com), 
               Jan 05 2006
%C A000988 Names for first few polyominoes: "monomino", "domino", "tromino", "tetromino", 
               "pentomino", "hexomino", "heptomino", "octomino", "enneomino", "decomino", 
               "hendecomino", "dodecomino", ...
%D A000988 S. W. Golomb, Polyominoes. Scribner's, NY, 1965; second edition ( Polyominoes: 
               Puzzles, Packings, Problems and Patterns) Princeton Univ. Press, 
               1994.
%D A000988 J. E. Goodman and J. O'Rourke, editors, Handbook of Discrete and Computational 
               Geometry, CRC Press, 1997, p. 229.
%D A000988 W. F. Lunnon, personal communication.
%D A000988 W. F. Lunnon, Counting multidimensional polyominoes. Computer Journal 
               18 (1975), no. 4, pp. 366-367.
%D A000988 Jaime Rangel-Mondragon, Polyominoes and Related Families, The Mathematica 
               Journal, 9:3 (2005), 609-640.
%D A000988 D. H. Redelmeier, Counting polyominoes: yet another attack, Discrete 
               Math., 36 (1981), 191-203.
%D A000988 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 
               (includes this sequence).
%D A000988 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, 
               Academic Press, 1995 (includes this sequence).
%H A000988 Toshihiro Shirakawa, <a href="b000988.txt">Table of n, a(n) for n=0 ..45</
               a>
%H A000988 Ed Pegg, Jr., <a href="http://demonstrations.wolfram.com/PolyformExplorer/
               ">Illustrations of polyforms</a>
%H A000988 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               Polyomino.html">Polyomino</a>
%Y A000988 See A006758 for another version. See also A030228 (chiral polyominoes), 
               A000105.
%Y A000988 Sequence in context: A099626 A046672 A046866 this_sequence A002214 A100408 
               A140562
%Y A000988 Adjacent sequences: A000985 A000986 A000987 this_sequence A000989 A000990 
               A000991
%K A000988 nonn
%O A000988 1,3
%A A000988 N. J. A. Sloane (njas(AT)research.att.com), hugh(AT)mimosa.com (D. Hugh 
               Redelmeier)