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%I M2496 #72 Jun 07 2017 15:25:23
%S 0,0,0,0,0,0,0,0,0,0,0,0,1,0,3,5,15,19,57,72,274,491,1766,3679,11158,
%T 24086,64754,132598,326042,667403,1627218,3508516
%N Number of simple imperfect squared squares of order n up to symmetry.
%C A squared rectangle (which may be a square) is a rectangle dissected into a finite number, two or more, of squares. If no two of these squares have the same size the squared rectangle is perfect. A squared rectangle is simple if it does not contain a smaller squared rectangle. The order of a squared rectangle is the number of constituent squares. - _Geoffrey H. Morley_, Oct 17 2012]
%C Orders 15 to 19 were enumerated by C. J. Bowkamp and A. J. W. Duijvestijn (1962). Orders 20 to 29 were enumerated by Stuart Anderson (2010-2012). Orders 30 to 32 were enumerated by Lorenz Milla and Stuart Anderson (2013). - _Stuart E Anderson_, Sep 30 2013
%D C. J. Bouwkamp, personal communication.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H Stuart Anderson, <a href="http://www.squaring.net/sq/ss/siss/siss.html">Simple Imperfect Squared Squares</a>.
%H C. J. Bouwkamp & N. J. A. Sloane, <a href="/A000162/a000162.pdf">Correspondence, 1971</a>
%H A. J. W. Duijvestijn, Electronic Computation of Squared Rectangles, Thesis, Technische Hogeschool, Eindhoven, Netherlands, 1962. Reprinted in <a href="http://alexandria.tue.nl/repository/books/44157.pdf">Philips Res. Rep., 17 (1962), 523-612</a>. [Pp. 573-4 have simple imperfect squares up to order 19.]
%H <a href="/index/Sq#squared_squares">Index entries for squared squares</a>
%Y Cf. A002839, A002881, A006983, A014530.
%Y Cf. A181735, A217155, A217156.
%K nonn,hard,nice
%O 1,15
%A _N. J. A. Sloane_
%E a(19) corrected and terms extended up to a(22) by _Stuart E Anderson_, Mar 08 2011
%E a(21) and a(22) corrected and terms extended to a(25) by _Stuart E Anderson_, Apr 24 2011
%E a(21), a(22), a(25) corrected and a(26)-a(28) added by _Stuart E Anderson_, Jul 11 2011
%E a(29) from _Stuart E Anderson_, _Ed Pegg Jr_, Stephen Johnson, Aug 22 2011
%E a(29) corrected by _Stuart E Anderson_, Aug 24 2011
%E Definition clarified and offset changed to 1 by _Geoffrey H. Morley_, Oct 17 2012
%E a(28) corrected by _Stuart E Anderson_, Dec 01 2012
%E a(30) from Lorenz Milla and _Stuart E Anderson_, Apr 10 2013
%E a(26) and a(29) corrected by _Stuart E Anderson_, Aug 20 2013
%E a(31), a(32) from Lorenz Milla and _Stuart E Anderson_, Sep 30 2013
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