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A280037
Denominators of fractions converging to limiting value of Galois polynomials.
3
1, 3, 5, 21, 1512, 15120, 30888, 16216200, 11762150400, 482718652416, 685679904000, 597828484915200, 2690228182118400000, 269791454835302400000, 191686828660482355200000, 25892338511873433600000, 129800853740753466163200000, 4685378150528730950270976000000
OFFSET
1,2
LINKS
Christian Günther, Kai-Uwe Schmidt, L^q norms of Fekete and related polynomials, arXiv:1602.01750 [math.NT], 2016.
EXAMPLE
1/1, 4/3, 11/5, 92/21, 15481/1512, 411913/15120, 2482927/30888, 4181926481/16216200, ...
MATHEMATICA
(* "gen" stands for "generalized Eulerian number" *)
gen[n_, x_] := Sum[(-1)^j Binomial[n + 1, j] (x + 1 - j)^n, {j, 0, Floor[x + 1]}];
c[k_] := c[k] = 1 - Sum[Binomial[k, j] Binomial[k - 1, j - 1] c[j], {j, 1, k - 1}];
G[0, 0] = 1; G[k_, m_] /; 1 <= m <= 2 k - 1 := G[k, m] = Sum[Binomial[k, j] Binomial[k - 1, j - 1] c[j]/(2 j - 1)! Sum[gen[2 j - 1, i - 1] G[k - j, m - i], {i, 0, m}], {j, 1, k}]; G[_, _] = 0;
Table[G[k, k] // Denominator, {k, 1, 18}] (* Jean-François Alcover, Sep 06 2018 *)
CROSSREFS
Cf. A280036. Related to central column of array in A280040.
Sequence in context: A153889 A364576 A186751 * A292557 A147442 A370580
KEYWORD
nonn,frac
AUTHOR
N. J. A. Sloane, Dec 28 2016
EXTENSIONS
a(9) and beyond from Lars Blomberg, Jul 07 2017
STATUS
approved