1,1

This is an equation related to a cantilever beam: cos(x)*cosh(x) = -1. The first three solutions are: 1.875 (A076417), 4.69409 (A076418) and 7.854757 (this sequence).

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

Z. Guede, I. Elishakov, 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.

cos(x) cosh(x) = -1, x = 7.854757...

(PARI) solve(x=7, 8, cos(x)*cosh(x) + 1) \\ Michel Marcus, Sep 11 2019

Cf. A076417, A076418.

Sequence in context: A003881 A225404 A320413 * A217516 A071420 A031139

Adjacent sequences: A076416 A076417 A076418 * A076420 A076421 A076422

easy,nonn,cons

Zak Seidov, Oct 10 2002

approved