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A076415
Decimal expansion of second solution of equation cos(x) cosh(x) = 1.
2
7, 8, 5, 3, 2, 0, 4, 6, 2, 4, 0, 9, 5, 8, 3, 7, 5, 5, 6, 4, 7, 7, 0, 6, 6, 6, 8, 7, 2, 5, 4, 0, 4, 9, 7, 9, 0, 3, 2, 2, 3, 0, 4, 1, 7, 3, 9, 9, 0, 6, 7, 4, 6, 1, 4, 8, 4, 1, 3, 3, 7, 3, 0, 8, 5, 1, 0, 5, 5, 9, 4, 1, 7, 8, 1, 9, 2, 9, 2, 8, 4, 9, 4, 8, 3, 8, 8, 6, 7, 6, 0, 0, 3, 1, 2, 4, 3, 8, 8, 4, 4, 1, 0, 2, 7
OFFSET
1,1
COMMENTS
This is an equation related to a beam clumped at both ends: cos(x) cosh(x) = 1. The first three solutions are: 4.73 (A076414), 7.853 (this sequence) and 10.996 (A076416).
LINKS
Z. Guede, I. Elishakov, A fifth-order polynomial that serves as both.., Chaos, Solitons and Fractals 12 (2001) 1267-1298.
EXAMPLE
cos(x) cosh(x) = 1, x = 7.8532...
MATHEMATICA
RealDigits[x/.FindRoot[Cos[x] Cosh[x]==1, {x, 5 Pi/2}, WorkingPrecision->120]][[1]] (* Jean-Francois Alcover, Mar 14 2011 *)
CROSSREFS
Sequence in context: A109916 A277053 A370466 * A190573 A216542 A216544
KEYWORD
easy,nonn,cons
AUTHOR
Zak Seidov, Oct 10 2002
STATUS
approved