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A076420
Decimal expansion of first solution of equation tan(x) = tanh(x).
2
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
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
Sequence in context: A309275 A179655 A357472 * A091473 A019675 A050129
KEYWORD
easy,nonn,cons
AUTHOR
Zak Seidov, Oct 10 2002
STATUS
approved