A076420 Decimal expansion of first solution of equation tan(x) = tanh(x).

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, 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, 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

Offset

1,1

Comments

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).

Links

Table of n, a(n) for n=1..105.

Zakoua Guédé and Isaac Elishakoff, A fifth-order polynomial that serves as both buckling and vibration mode of an inhomogeneous structure, Chaos, Solitons and Fractals 12 (7) (2001) 1267-1298.

Example

3.92660231204791877823853334362702489516115208699533...

Mathematica

RealDigits[x /. FindRoot[Tan[x] == Tanh[x], {x, 4}, WorkingPrecision->120], 10, 105][[1]] (* Amiram Eldar, May 02 2023 *)

Prog

(PARI) solve(x = 3, 4, tan(x) - tanh(x)) \\ Amiram Eldar, May 02 2023

Crossrefs

Cf. A076421, A076422.

Sequence in context: A309275 A179655 A357472 * A091473 A019675 A050129

Adjacent sequences: A076417 A076418 A076419 * A076421 A076422 A076423

Keyword

easy,nonn,cons

Author

Zak Seidov, Oct 10 2002

Status

approved