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A002195
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Numerators of coefficients for numerical integration.
(Formerly M4809 N2056)
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9
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1, -1, 11, -191, 2497, -14797, 92427157, -36740617, 61430943169, -23133945892303, 16399688681447, -3098811853954483, 312017413700271173731, -69213549869569446541, 53903636903066465730877, -522273861988577772410712439, 644962185719868974672135609261
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OFFSET
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0,3
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COMMENTS
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The numerators of these coefficients for numerical integration are a combination of the Bernoulli numbers B{2k}, the central factorial numbers A008955(n, k) and the factor (2n+1)!. - Johannes W. Meijer, Jan 27 2009
These numbers are the numerators of the constant term in the Laurent expansion of the cosech^(2n)(x)/2^(2n) function. - Istvan Mezo, Apr 21 2023
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REFERENCES
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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).
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LINKS
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FORMULA
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a(n) = numerator of (2/(2*n+1)!)*Integral_{t=0..1} t*Product_{k=1..n} t^2-k^2. - Emeric Deutsch, Jan 25 2005
a(0) = 1; a(n) = numerator [sum((-1)^(k+n+1) * (B{2k}/(2*k)) * A008955(n-1, n-k), k = 1..n)/(2*n-1)!] for n >= 1. - Johannes W. Meijer, Jan 27 2009
a(n) = numerator(sum(k=1..2*n, binomial(2*n+k-1,2*n-1)*sum(j=1..k, (binomial(k,j)*sum(i=0,j/2, (2*i-j)^(2*n+j)*binomial(j,i)*(-1)^(-i)))/(2^j*(2*n+j)!)))), n>0, a(0)=1. - Vladimir Kruchinin, Feb 04 2013
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EXAMPLE
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a(1) = -1 because (1/3)*int(t*(t^2-1^2),t=0..1) = -1/12.
a(3) = numer((-((1/6)/2)*(4) +((-1/30)/4)*(5) - ((1/42)/6)*(1))/5!) so a(3) = -191. - Johannes W. Meijer, Jan 27 2009
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MAPLE
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a:=n->numer((2/(2*n+1)!)*int(t*product(t^2-k^2, k=1..n), t=0..1)): seq(a(n), n=0..16); # Emeric Deutsch, Feb 20 2005
nmax:=16: with(combinat): A008955 := proc(n, k): sum((-1)^j*stirling1(n+1, n+1-k+j) * stirling1(n+1, n+1-k-j), j = -k..k) end proc: Omega(0) := 1: for n from 1 to nmax do Omega(n) := sum((-1)^(k1+n+1)*(bernoulli(2*k1)/(2*k1))* A008955(n-1, n-k1), k1=1..n)/(2*n-1)! end do: a := n-> numer(Omega(n)): seq(a(n), n=0..nmax); # Johannes W. Meijer, Jan 27 2009, Revised Sep 21 2012
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MATHEMATICA
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a[0] = 1; a[n_] := Sum[Binomial[2*n+k-1, 2*n-1]*Sum[Binomial[k, j]*Sum[(2*i-j)^(2*n+j)*Binomial[j, i]*(-1)^(-i), {i, 0, j/2}]/(2^j*(2*n+j)!), {j, 1, k}], {k, 1, 2*n}]; Table[a[n] // Numerator, {n, 0, 16}] (* Jean-François Alcover, Apr 18 2014, after Vladimir Kruchinin *)
a[n_] := Numerator[SeriesCoefficient[1/2^(2*n)*Csch[x]^(2*n), {x, 0, 0}]] (* Istvan Mezo, Apr 21 2023 *)
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PROG
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(Maxima)
a(n):=num(sum(binomial(2*n+k-1, 2*n-1)*sum((binomial(k, j)*sum((2*i-j)^(2*n+j)*binomial(j, i)*(-1)^(-i), i, 0, j/2))/(2^j*(2*n+j)!), j, 1, k), k, 1, 2*n)); \\ Vladimir Kruchinin, Feb 04 2013
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CROSSREFS
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KEYWORD
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sign,frac
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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