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A000411 Generalized tangent numbers d(6,n).
(Formerly M4312 N1805)
3

%I M4312 N1805

%S 6,522,152166,93241002,97949265606,157201459863882,357802951084619046,

%T 1096291279711115037162,4350684698032741048452486,

%U 21709332137467778453687752842,133032729004732721625426681085926,982136301747914281420205946546842922

%N Generalized tangent numbers d(6,n).

%D N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

%H Lars Blomberg, <a href="/A000411/b000411.txt">Table of n, a(n) for n = 1..184</a>

%H D. Shanks, <a href="http://dx.doi.org/10.1090/S0025-5718-1967-0223295-5">Generalized Euler and class numbers</a>. Math. Comp. 21 1967 663-688.

%H D. Shanks, <a href="http://dx.doi.org/10.1090/S0025-5718-1968-0227093-9">Corrigenda to: "Generalized Euler and class numbers"</a>, Math. Comp. 22 (1968), 699

%H D. Shanks, <a href="/A000003/a000003.pdf">Generalized Euler and class numbers</a>, Math. Comp. 21 (1967), 689-694; 22 (1968), 699. [Annotated scanned copy]

%t nmax = 15; km0 = 10; Clear[dd]; L[a_, s_, km_] := Sum[JacobiSymbol[-a, 2 k + 1]/(2 k + 1)^s, {k, 0, km}]; d[a_ /; a > 1, n_, km_] := (2 n - 1)! L[-a, 2 n, km] (2 a/Pi)^(2 n)/Sqrt[a] // Round; dd[km_] := dd[km] = Table[d[6, n, km], {n, 1, nmax}]; dd[km0]; dd[km = 2 km0]; While[dd[km] != dd[km/2, km = 2 km]]; A000411 = dd[km] (* _Jean-Fran├žois Alcover_, Feb 08 2016 *)

%Y Cf. A000320.

%K nonn

%O 1,1

%A _N. J. A. Sloane_

%E a(10)-a(12) from _Lars Blomberg_, Sep 07 2015

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Last modified December 11 05:41 EST 2017. Contains 295868 sequences.