A343169 - OEIS

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A343169

Number of sporadic maximal rational-angle line configurations with n lines, up to equivalence.

0, 228, 29, 22, 0, 5, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0

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OFFSET

3,2

COMMENTS

In dimensions 3 through 6 there are also one- or two-parameter families of solutions.

a(n) = 0 for n > 15, except a(aleph-0) = 1 (the perpendicular configuration).

LINKS

Table of n, a(n) for n=3..125.

K. S. Kedlaya, A. Kolpakov, B. Poonen, and M. Rubinstein, Space vectors forming rational angles, arXiv preprint arXiv:2011.14232 [math.MG], 2020.

CROSSREFS

Sequence in context: A092324 A122976 A098245 * A190027 A090943 A252451

Adjacent sequences: A343166 A343167 A343168 * A343170 A343171 A343172

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Apr 20 2021

STATUS

approved