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 A222072 Decimal expansion of (1/384)*Pi^4. 13
 2, 5, 3, 6, 6, 9, 5, 0, 7, 9, 0, 1, 0, 4, 8, 0, 1, 3, 6, 3, 6, 5, 6, 3, 3, 6, 6, 3, 7, 6, 8, 3, 6, 2, 2, 7, 2, 1, 2, 8, 3, 2, 2, 5, 4, 3, 5, 5, 9, 5, 1, 6, 1, 8, 9, 8, 8, 1, 9, 7, 5, 5, 0, 4, 9, 4, 7, 1, 5, 7, 6, 9, 4, 1, 8, 8, 2, 0, 8, 2, 3, 4, 1, 1, 7, 7, 5, 6, 9, 5, 9, 2, 3, 8, 3, 5, 9, 1, 8, 1, 0, 1 (list; constant; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS Conjectured to be density of densest packing of equal spheres in 8 dimensions (achieved for example by the D_8 lattice). The above conjecture is true (cf. Viazovska, 2017). - Felix Fröhlich, Jan 08 2018 REFERENCES J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer, 3rd. ed., 1998. See p. xix. LINKS Table of n, a(n) for n=0..101. J. H. Conway and N. J. A. Sloane, What are all the best sphere packings in low dimensions?, Discrete & Computational Geometry, Vol. 13, No. 3-4 (1995), 383-403. G. Nebe and N. J. A. Sloane, Home page for E_8 lattice N. J. A. Sloane, Table of maximal density of a packing of equal spheres in n-dimensional Euclidean space (for n>3 the values are only conjectural). Maryna S. Viazovska, The sphere packing problem in dimension 8, Annals of Mathematics, Vol. 185, No. 3 (2017), 991-1015. Maryna S. Viazovska, The sphere packing problem in dimension 8, arXiv:1603.04246 [math.NT], 2017. Index entries for transcendental numbers FORMULA Equals Sum_{n>=1} Sum_{k>=n} 1/(2*n - 1)^2/(2*k + 1)^2. - Geoffrey Critzer, Nov 03 2013 EXAMPLE .25366950790104801363656336637683622721283225435595161898819... MATHEMATICA RealDigits[Pi^4/ 384, 10, 120][[1]] (* Harvey P. Dale, Aug 11 2015 *) PROG (PARI) Pi^4/384 \\ Charles R Greathouse IV, Oct 31 2014 CROSSREFS Related constants: A020769, A020789, A093766, A093825, A222066, A222067, A222068, A222069, A222070, A222071, A222073, A222074, A222075. Sequence in context: A341492 A264105 A024871 * A246007 A256997 A335499 Adjacent sequences: A222069 A222070 A222071 * A222073 A222074 A222075 KEYWORD nonn,cons AUTHOR N. J. A. Sloane, Feb 10 2013 STATUS approved

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Last modified December 9 04:27 EST 2023. Contains 367681 sequences. (Running on oeis4.)