This site is supported by donations to The OEIS Foundation. Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A002680 Denominators of coefficients of polynomials arising from Chebyshev quadrature. (Formerly M2261 N0892) 3
 1, 1, 3, 2, 45, 72, 105, 6480, 42525, 22400, 56133, 32659200, 7882875, 452656512000, 351833625, 129153024, 4396161144375, 8473729904640000, 9901766875, 54452188367216640000, 4167666272734965, 168568418304000000, 7426884628582453125, 20484913263746899968000000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 REFERENCES C. A. Pickover, The Math Book, Sterling, NY, 2009; see p. 184. 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 Petros Hadjicostas, Table of n, a(n) for n = 0..30 H. E. Salzer, Tables for facilitating the use of Chebyshev's quadrature formula, Journal of Mathematics and Physics, 26 (1947), 191-194. Eric Weisstein's World of Mathematics, Chebyshev Quadrature MAPLE s := proc(z) 1/6*z^2*hypergeom([1, 1, 3/2], [2, 5/2], z^2); end proc; f:= proc(n) local v, m; v := 1;      for m to n do      v := lcm(v, denom(coeftayl(exp(-n*s(z)), z = 0, m))); end do; v;      end proc; seq(f(n), n = 0 .. 26); # Petros Hadjicostas, Oct 28 2019 MATHEMATICA gf[n_, z_] := Exp[n (ArcTanh[z]/z + Log[1 - z^2]/2 - 1)]; ser[n_] := CoefficientList[Series[gf[n, z], {z, 0, n}], z]; Table[LCM @@ Denominator[ser[n]], {n, 0, 30}] (* Peter Luschny, Oct 28 2019 *) CROSSREFS Numerators appear in A101270 (with zeros for the missing powers) and in A324123 (without the zeros for the missing powers and with the highest powers first). Sequence in context: A065085 A321169 A093398 * A009395 A226769 A093892 Adjacent sequences:  A002677 A002678 A002679 * A002681 A002682 A002683 KEYWORD nonn,easy,frac AUTHOR EXTENSIONS More terms from Pab Ter (pabrlos(AT)yahoo.com), May 11 2004 a(22)-a(30) from Petros Hadjicostas, Oct 28 2019 a(0) = 1 prepended by Petros Hadjicostas, Oct 28 2019 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified November 14 19:59 EST 2019. Contains 329128 sequences. (Running on oeis4.)