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%I #24 Dec 07 2018 12:30:32
%S 1,0,0,136,1326,8160,31552,88128,240618,658784,1452480,2622216,
%T 5030028,10390944,18128256,26822464,43527174,77769696,119299200,
%U 157895592,232127928,379052672,537564480,662425536,910537442,1402281312,1881950592,2201578336,2894860164,4268628192,5501926784
%N Theta series of 17-dimensional lattice Q'_17(6)^{+2}.
%H J. H. Conway and N. J. A. Sloane, <a href="https://www.jstor.org/stable/2398331">Low-Dimensional Lattices II: Subgroups of GL(n,Z)</a>, Proc. Royal Soc. London, A 419 (1988), 29-68.
%H Gheorghe Coserea, <a href="/A015163/a015163.txt">Gram matrix</a>.
%H G. Nebe and N. J. A. Sloane, <a href="http://www.math.rwth-aachen.de/~Gabriele.Nebe/LATTICES/Qp1762.html">Home page for this lattice</a>
%H W. Plesken, <a href="https://core.ac.uk/download/pdf/82549703.pdf">Finite Unimodular Groups of Prime Degree and Circulants</a>, J. Algebra, vol. 97 (1985), pp. 286-312.
%o (PARI) \\ system("wget https://oeis.org/A015163/a015163.txt");
%o g = matconcat(read("a015163.txt")~);
%o seq(N, g, flag=0) = concat(1, 2*Vec(qfrep(g, N, flag)));
%o seq(15, g) \\ _Gheorghe Coserea_, Nov 28 2018
%o (PARI)
%o GramMatrix()={my(p=[3, -1, 0, 0, 1, -1, 0, 1, 0, 0, 1, 0, -1, 1, 0, 0, -1]); matrix(#p, #p, i, j, p[(i-j) %#p + 1])}
%o a(n)={if(n==0, 1, 2*qfrep(GramMatrix(), n, 0)[n])} \\ _Andrew Howroyd_, Nov 29 2018
%Y Cf. A015158, A015159, A015160, A015161, A015162, A015164, A015165.
%K nonn
%O 0,4
%A _N. J. A. Sloane_
%E More terms from _Gheorghe Coserea_, Nov 28 2018
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