%I #17 Feb 29 2020 15:16:16
%S 1,0,2,2676,101118,1644784,16044996,110148864,584716268,2549726784,
%T 9515920164,31314134428,92917720104,252775518960,638328487880,
%U 1511740834560,3387163064214,7228599229760,14768913424614,29023937463900,55107648867544,101434033397472
%N Theta series of 27-dimensional unimodular lattice with root system A_1 with no parity vector of norm 3.
%D R. Bacher and B. B. Venkov, Réseaux entiers unimodulaires sans racine en dimension 27 et 28, in Réseaux euclidiens, designs sphériques et formes modulaires, pp. 212-267, Enseignement Math., Geneva, 2001.
%H R. Bacher and B. B. Venkov, <a href="https://www-fourier.univ-grenoble-alpes.fr/?q=fr/content/reseaux-entiers-unimodulaires-sans-racine-en-dimension-27-et-28">Réseaux entiers unimodulaires sans racine en dimension 27 et 28</a>
%F G.f.: theta3^27 - 54*theta3^19*delta8 + 218*theta3^11*delta8^2 where theta3 = A000122 and delta8 = A002408. - _Sean A. Irvine_, Feb 28 2020
%Y Cf. A000122, A002408, A002434, A002490.
%K nonn
%O 0,3
%A _N. J. A. Sloane_
%E More terms from _Sean A. Irvine_, Feb 28 2020