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 A001309 Order of real Clifford group L_n connected with Barnes-Wall lattices in dimension 2^n. 12
 2, 16, 2304, 5160960, 178362777600, 96253116206284800, 819651496316379542323200, 110857799304670627788849414144000, 238987988705420266773820308079698247680000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 LINKS G. Nebe, E. M. Rains and N. J. A. Sloane, Self-Dual Codes and Invariant Theory, Springer, Berlin, 2006. A. R. Calderbank, E. M. Rains, P. W. Shor and N. J. A. Sloane, Quantum error correction via codes over GF(4), IEEE Trans. Inform. Theory, 44 (1998), 1369-1387. G. Nebe, E. M. Rains and N. J. A. Sloane, The invariants of the Clifford groups, Des. Codes Crypt. 24 (2001), 99-121. MAPLE 2^(n^2+n+2) * (2^n - 1) * product('2^(2*i)-1', 'i'=1..n-1); MATHEMATICA a[0] = 2; a[n_] := 2^(n^2+n+2) * (2^n-1) * Product[2^(2*i)-1, {i, 1, n-1}]; Table[a[n], {n, 0, 8}] (* Jean-François Alcover, Jul 16 2015, after Maple *) CROSSREFS 2^(2n+2) times order of Chevalley group D_n (2) (cf. A001308). Twice A014115. See also A014116, A003956 (for the complex group). Sequence in context: A060597 A091479 A016031 * A132569 A165644 A203315 Adjacent sequences:  A001306 A001307 A001308 * A001310 A001311 A001312 KEYWORD nonn,easy,nice AUTHOR STATUS approved

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Last modified December 16 12:37 EST 2018. Contains 318160 sequences. (Running on oeis4.)