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%I
%S 1,0,1800,0,541200,0,65520920,0,4296107040,0,177923724072,0,
%T 5119703270960,0,109262828065080,536870912,1814093339150400,
%U 249644974080,24305082449321800,21968757719040,270526359458466384
%N Coordination sequence for diamond structure D^+_30. (Edges defined by l_1 norm = 1.)
%D J. Serra-Sagrista, Enumeration of lattice points in l_1 norm, Information Processing Letters, 76, no. 1-2 (2000), 39-44.
%H J. H. Conway and N. J. A. Sloane, Low-Dimensional Lattices VII: Coordination Sequences, Proc. Royal Soc. London, A453 (1997), 2369-2389 (<a href="http://neilsloane.com/doc/Me220.pdf">pdf</a>).
%p f := proc(m) local k,t1; t1 := 2^(n-1)*binomial((n+2*m)/2-1,n-1); if m mod 2 = 0 then t1 := t1+add(2^k*binomial(n,k)*binomial(m-1,k-1),k=0..n); fi; t1; end; where n=30.
%K nonn
%O 0,3
%A Joan Serra-Sagrista (jserra(AT)ccd.uab.es)
%E Recomputed by _N. J. A. Sloane_, Nov 27 1998
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