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A004673
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Theta series of extremal even unimodular lattice in dimension 56.
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2
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1, 0, 0, 15590400, 36957286800, 15284192071680, 2099603881267200, 134803322124134400, 4960017097962973200, 119289241340847513600, 2051414989573311774720, 26894038407511734144000, 281804009505443595441600
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listen;
history;
text;
internal format)
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OFFSET
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0,4
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REFERENCES
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J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 195.
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LINKS
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FORMULA
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E4^7 - 1680 * E4^4 * Delta + 347760 * E4 * Delta^2 with E4(q) as in A004009 and Delta(q) as in A000594. - Andy Huchala, Jun 05 2021
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EXAMPLE
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G.f.: 1 + 15590400*q^3 + 36957286800*q^4 + ...
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PROG
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(Sage)
e4 = eisenstein_series_qexp(4, 20, normalization = "integral");
delta = CuspForms(1, 12).0.q_expansion(20);
e4^7 - 1680*e4^4*delta + 347760*e4*delta^2 # Andy Huchala, Jun 05 2021
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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