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A346159
Number of n-dimensional representations of the group SU(3).
0
1, 1, 1, 3, 3, 3, 8, 8, 9, 17, 19, 21, 35, 39, 44, 68, 79, 87, 127, 145, 162, 228, 261, 291, 395, 451, 506, 665, 760, 850, 1096, 1254, 1400, 1765, 2016, 2249, 2800, 3188, 3556, 4356, 4953, 5522, 6688, 7581, 8447, 10123, 11464, 12747, 15141, 17094, 18997, 22395
OFFSET
0,4
FORMULA
G.f.: Product_{j,k>=1} 1/(1-x^(j*k*(j+k)/2)).
PROG
(PARI) fij(lim) = my(imax = ceil((sqrt(8*lim+1)-1)/2), list=List()); for (i=1, imax, for (j=1, imax, if ((p=i*j*(i+j)/2) <= lim, listput(list, p)))); list;
lista(nn) = my(v=fij(nn), x='x+O('x^nn), w=Vec(prod(k=1, #v, 1/(1-x^v[k])))); vector(nn, k, w[k]);
CROSSREFS
Cf. A107985 (as a rectangular array).
Sequence in context: A111521 A177937 A029628 * A241739 A226509 A329694
KEYWORD
nonn
AUTHOR
Michel Marcus, Jul 08 2021
STATUS
approved