

A131976


Let G be the full icosahedral group, of order 120. Let v_1, ..., v_20 be the vertices of the dodecahedron. Let S(n) be the set of vectors v_{i_1} + v_{i_2} + ... + v_{i_n} where 1 <= i_1 <= i_2 <= ... <= i_n <= 20. Then a(n) = number of orbits of G on S(n).


1



1, 1, 5, 12, 22, 34, 50, 65, 78, 78, 86, 78, 78, 65, 50, 34, 22, 12, 5, 1, 1
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OFFSET

0,3


LINKS



EXAMPLE

For 2 vertices, there are 5 different sets:
{10 pairs with norm^2 of sum = 0.000}
{30 pairs with 1.000}
{60, 2.618}
{60, 5.236}
{30, 6.854}
the norm^2 is taken with the side of the pentagons = 1.
And of course 10+30+60+60+30 = 190 = 20 choose 2


CROSSREFS



KEYWORD

nonn,fini,full


AUTHOR



EXTENSIONS



STATUS

approved



