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A169955
Number of tau-isomorphism classes of spherical bitrades with |T0| = n.
1
1, 0, 3, 1, 6, 9, 30, 51, 198, 470, 1623, 4830, 16070, 51948, 175047, 588120, 2015226, 6933048, 24123941, 84428820, 297753519
OFFSET
4,3
LINKS
Ales Drapal, Carlo Hamalainen and Dan Rosendorf, An enumeration of spherical latin bitrades, arXiv:0907.1376 [math.CO], Sep 16 2009.
Carlo Hamalainen, Enumeration of spherical bitrades, archive of C++ code, Sept 15, 2009.
CROSSREFS
Sequence in context: A020861 A163213 A095066 * A084536 A110770 A106855
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Aug 01 2010
EXTENSIONS
Offset corrected and a(4)-a(5) added by Hugo Pfoertner, Aug 11 2017
STATUS
approved