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A076417
Decimal expansion of first solution of equation cos(x)*cosh(x) = -1.
7
1, 8, 7, 5, 1, 0, 4, 0, 6, 8, 7, 1, 1, 9, 6, 1, 1, 6, 6, 4, 4, 5, 3, 0, 8, 2, 4, 1, 0, 7, 8, 2, 1, 4, 1, 6, 2, 5, 7, 0, 1, 1, 1, 7, 3, 3, 5, 3, 1, 0, 6, 9, 9, 8, 8, 2, 4, 5, 4, 1, 3, 7, 1, 3, 1, 0, 5, 6, 7, 9, 9, 5, 2, 8, 4, 0, 4, 2, 8, 6, 3, 8, 5, 2, 6, 5, 6, 6, 5, 5, 0, 5, 8, 1, 8, 8, 6, 0, 3, 7, 0, 8, 4, 1, 0
OFFSET
1,2
COMMENTS
This is an equation related to a cantilever beam: cos(x)*cosh(x) = -1. The first three solutions are: 1.875 (this sequence), 4.69409 (A076418) and 7.854757 (A076419).
LINKS
EXAMPLE
1.87510406871196116644530824107821416257011173353...
MATHEMATICA
RealDigits[x/.FindRoot[Cos[x]Cosh[x]==-1, {x, 1.8}, WorkingPrecision->120], 10, 120][[1]] (* Harvey P. Dale, Jul 24 2011 *)
PROG
(PARI) solve(x=1, 2, cos(x)*cosh(x) + 1) \\ Michel Marcus, Sep 11 2019
CROSSREFS
KEYWORD
easy,nonn,cons
AUTHOR
Zak Seidov, Oct 10 2002
STATUS
approved