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 A108778 Continued fraction expansion of the Madelung constant for the NaCl structure (A085469). 2
 1, 1, 2, 1, 24, 1, 10, 1, 1, 52, 1, 8, 1, 1, 1, 4, 2, 27, 2, 3, 1, 4, 1, 1, 1, 4, 2, 2, 1, 3, 1, 2, 1, 2, 1, 1, 3, 1, 51, 1, 4, 3, 3, 4, 1, 2, 1, 14, 1, 1, 1, 1, 1, 4, 7, 1, 3, 38, 4, 1, 2, 1, 2, 1, 1, 1, 6, 4, 5, 1, 14, 2, 18, 1, 10, 2, 5, 2, 2, 2, 9, 1, 4, 1, 23, 1, 2, 1, 2, 3, 132, 343, 2, 1, 1, 4, 3, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Increasing PQ's: 1, 2, 24, 52, 132, 343, 664, 1329, 2136, .... LINKS Harry J. Smith, Table of n, a(n) for n = 1..1794 EXAMPLE 1.7475645946331821906362... = 1 + 1/(1 + 1/(2 + 1/(1 + 1/(24 + ...)))). - Harry J. Smith, Apr 23 2009 MATHEMATICA ContinuedFraction[ 12Pi*Sum[ Sech[ Pi/2*Sqrt[(2j + 1)^2 + (2k + 1)^2]]^2, {j, 0, 36}, {k, 0, 36}], 98] CROSSREFS Cf. A085469. Sequence in context: A255861 A059360 A279308 * A271530 A062763 A243147 Adjacent sequences:  A108775 A108776 A108777 * A108779 A108780 A108781 KEYWORD cofr,nonn AUTHOR Robert G. Wilson v, Jul 18 2005 EXTENSIONS Definition corrected by Leslie Glasser, Jan 24 2011 Definition corrected by Andrey Zabolotskiy, Jul 30 2020 STATUS approved

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Last modified April 14 21:21 EDT 2021. Contains 342962 sequences. (Running on oeis4.)