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 A221841 Number of ways to dissect a square into n squares up to symmetry. 2
 1, 0, 0, 1, 0, 1, 2, 6, 16, 56, 183, 657, 2277, 8813, 34178, 137578, 558734, 2285694 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,7 LINKS Ed Wynn, Exhaustive generation of Mrs Perkins's quilt square dissections for low orders, 2013, arXiv:1308.5420 EXAMPLE For n = 7 there are a(7) = 2 ways: +---+---+   +---+---+ |   |   |   |   |   | |   |   |   |   |   | |   |   |   |   |   | +-+-+-+-+   +---+-+-+ | |   | |   |   | | | +-+   +-+   |   +-+-+ | |   | |   |   | | | +-+---+-+   +---+-+-+ CROSSREFS Cf. A221840, A221842. Sequence in context: A147919 A320805 A150029 * A068787 A073959 A006820 Adjacent sequences:  A221838 A221839 A221840 * A221842 A221843 A221844 KEYWORD nonn,nice,more AUTHOR Geoffrey H. Morley, Jan 26 2013 EXTENSIONS a(10) corrected (thanks to Ed Wynn) by Geoffrey H. Morley, Aug 02 2013 More terms from Wynn, 2013. - N. J. A. Sloane, Nov 29 2013 STATUS approved

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Last modified October 23 05:56 EDT 2019. Contains 328335 sequences. (Running on oeis4.)