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%I #12 May 02 2023 02:26:26
%S 3,9,2,6,6,0,2,3,1,2,0,4,7,9,1,8,7,7,8,2,3,8,5,3,3,3,4,3,6,2,7,0,2,4,
%T 8,9,5,1,6,1,1,5,2,0,8,6,9,9,5,3,3,7,3,0,7,4,2,0,6,6,8,6,5,4,2,5,5,2,
%U 7,9,7,0,8,9,0,9,6,4,6,4,2,4,7,4,1,9,4,3,3,8,0,0,1,5,6,2,1,9,4,2,2,0,5,1,3
%N Decimal expansion of first solution of equation tan(x) = tanh(x).
%C This is an equation related to a beam clamped at left and simply supported at right: tan(x) = tanh(x). The first three solutions are: 3.9266... (this sequence), 7.0686... (A076421) and 10.21... (A076422).
%H Zakoua Guédé and Isaac Elishakoff, <a href="http://dx.doi.org/10.1016/S0960-0779(00)00014-X">A fifth-order polynomial that serves as both buckling and vibration mode of an inhomogeneous structure</a>, Chaos, Solitons and Fractals 12 (7) (2001) 1267-1298.
%e 3.92660231204791877823853334362702489516115208699533...
%t RealDigits[x /. FindRoot[Tan[x] == Tanh[x], {x, 4}, WorkingPrecision->120], 10, 105][[1]] (* _Amiram Eldar_, May 02 2023 *)
%o (PARI) solve(x = 3, 4, tan(x) - tanh(x)) \\ _Amiram Eldar_, May 02 2023
%Y Cf. A076421, A076422.
%K easy,nonn,cons
%O 1,1
%A _Zak Seidov_, Oct 10 2002
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