A169955 Number of tau-isomorphism classes of spherical bitrades with |T0| = n.

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

Table of n, a(n) for n=4..24.

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

Cf. A007083, A167123.

Sequence in context: A020861 A163213 A095066 * A084536 A110770 A106855

Adjacent sequences: A169952 A169953 A169954 * A169956 A169957 A169958

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