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 A029681 Theta series of quadratic form with Gram matrix [ 2, 1, 0; 1, 2, 1; 0, 1, 3 ]. 2
 1, 0, 6, 6, 0, 6, 6, 12, 6, 0, 6, 12, 6, 6, 24, 12, 0, 0, 18, 6, 6, 14, 12, 24, 6, 0, 18, 24, 12, 12, 12, 12, 6, 0, 12, 42, 0, 12, 30, 12, 6, 0, 42, 12, 12, 18, 12, 36, 6, 0, 30, 12, 6, 24, 24, 12, 24, 0, 24, 30, 12, 6, 36, 60, 0, 0, 12, 24, 0, 12, 42, 36, 18, 0, 24, 30, 6, 48, 36, 12, 6, 0, 24 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS The Gram matrix [ 2, 1, 1; 1, 2, 1; 1, 1, 3 ] defines the same lattice. This is the trigonal R lattice (the classical holotype) of dimension 3. LINKS John Cannon, Table of n, a(n) for n = 0..9999 G. Nebe and N. J. A. Sloane, Home page for this lattice EXAMPLE 1 + 6*q^2 + 6*q^3 + 6*q^5 + 6*q^6 + 12*q^7 + 6*q^8 + 6*q^10 + 12*q^11 + 6*q^12 + ... CROSSREFS Sequence in context: A272648 A212708 A028969 * A109917 A153629 A154155 Adjacent sequences: A029678 A029679 A029680 * A029682 A029683 A029684 KEYWORD nonn AUTHOR N. J. A. Sloane. STATUS approved

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Last modified May 31 11:21 EDT 2023. Contains 363066 sequences. (Running on oeis4.)