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%I #27 Dec 07 2018 12:30:50
%S 1,0,0,0,102,0,1326,9792,0,31552,122196,0,240618,992256,0,1452480,
%T 4163742,0,5030028,17109888,0,18128256,45317988,0,43527174,134013312,
%U 0,119299200,276648888,0,232127928,672628800,0,537564480,1186603368,0,910537442,2535618816,0,1881950592,4014830772,0,2894860164,7826947968,0,5501926784,11452412304,0,7880557842,20846939520,0
%N Theta series of 17-dimensional lattice Q'_17(6)^{+3}.
%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="/A015164/a015164.txt">Gram matrix</a>.
%H G. Nebe and N. J. A. Sloane, <a href="http://www.math.rwth-aachen.de/~Gabriele.Nebe/LATTICES/Qp1763.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.
%e 1 + 102*q^8 + 1326*q^12 + 9792*q^14 + 31552*q^18 + 122196*q^20 + 240618*q^24 + 992256*q^26 + 1452480*q^30 + ...
%o (PARI) \\ system("wget https://oeis.org/A015164/a015164.txt");
%o g = matconcat(read("a015164.txt")~);
%o seq(N, g, flag=0) = concat(1, 2*Vec(qfrep(g, N, flag)));
%o seq(22, g, 1) \\ _Gheorghe Coserea_, Nov 28 2018
%o (PARI)
%o GramMatrix()={my(p=[8 ,-1 ,-1 ,-1 ,-1 ,-1 ,2 ,2 ,-1 ,-1 ,2 ,2 ,-1 ,-1 ,-1 ,-1 ,-1]); matrix(#p, #p, i, j, p[(i-j) %#p + 1])}
%o a(n)={if(n==0, 1, 2*qfrep(GramMatrix(), n, 1)[n])} \\ _Andrew Howroyd_, Nov 29 2018
%Y Cf. A015158, A015159, A015160, A015161, A015162, A015163, A015165.
%K nonn
%O 0,5
%A _N. J. A. Sloane_
%E More terms from _Gheorghe Coserea_, Nov 28 2018
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