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 A351831 Vector in the 26-dimensional even Lorentzian unimodular lattice II_25,1 used to construct the Leech lattice. 2
 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 70 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS As noted by Conway and Sloane (1999), the only nontrivial solution of 0^2 + 1^2 + ... + m^2 = n^2 in positive integers is m = 24, n = 70, allowing them to use the vector (0, 1, 2, 3, ..., 23, 24 | 70) to construct the Leech lattice. LINKS Table of n, a(n) for n=1..26. Richard E. Borcherds, How to construct the Leech lattice, YouTube video, 2022. J. H. Conway and N. J. A. Sloane, Lorentzian forms for the Leech lattice, Bulletin (New Series) of the American Mathematical Society, Volume 6, Number 2, March 1982. J. H. Conway and N. J. A. Sloane, Sphere Packings, Lattices and Groups, 3rd edition, Springer, New York, NY, 1999, pp. 524-528. Wikipedia, II_25,1. Wikipedia, Leech lattice. MATHEMATICA Append[Range[0, 24], 70] CROSSREFS Cf. A008408, A260646, A351830. Sequence in context: A090273 A135381 A135382 * A328617 A230308 A357875 Adjacent sequences: A351828 A351829 A351830 * A351832 A351833 A351834 KEYWORD nonn,easy,fini,full AUTHOR Paolo Xausa, Feb 21 2022 STATUS approved

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Last modified August 9 16:51 EDT 2024. Contains 375044 sequences. (Running on oeis4.)