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 A002298 Denominator of (2/Pi)*Integral_{0..inf} (sin x / x)^n dx. (Formerly M3217 N1303) 5
 1, 1, 4, 3, 192, 20, 11520, 315, 573440, 36288, 928972800, 1663200, 54499737600, 74131200, 1322526965760, 6810804000, 228532659683328000, 37638881280, 16783438527143608320, 121645100408832, 30370031620545576960000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Except for the n=4 term, equal to A049331/2. REFERENCES N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence). N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). LINKS T. D. Noe, Table of n, a(n) for n=1..100 A. H. R. Grimsey, On the accumulation of chance effects and the Gaussian frequency distribution, Phil. Mag., 36 (1945), 294-295. R. G. Medhurst and J. H. Roberts, Evaluation of the integral I_n(b) = (2/Pi)*Integral_{0..inf} (sin x / x)^n cos (bx) dx, Math. Comp., 19 (1965), 113-117. EXAMPLE 1, 1, 3/4, 2/3, 115/192, 11/20, ... MATHEMATICA Denominator[Table[2/Pi Integrate[(Sin[x]/x)^n, {x, 0, \[Infinity]}], {n, 25}]] (* Harvey P. Dale, Sep 04 2011 *) Denominator@Table[Sum[(-1)^k (n-2k)^(n-1) Binomial[n, k], {k, 0, n/2}]/((n-1)! 2^(n-1)), {n, 1, 30}] (* Vladimir Reshetnikov, Sep 02 2016 *) CROSSREFS Cf. A002297, A002304, A002305. Sequence in context: A300026 A266255 A079324 * A195565 A197243 A175372 Adjacent sequences:  A002295 A002296 A002297 * A002299 A002300 A002301 KEYWORD nonn,frac,easy,nice AUTHOR EXTENSIONS Corrected and extended by Barbara Haas Margolius (margolius(AT)math.csuohio.edu), Dec 02 2001 STATUS approved

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Last modified June 16 19:43 EDT 2019. Contains 324155 sequences. (Running on oeis4.)