A196604 Decimal expansion of the least x>0 satisfying sec(x)=3x.

3, 5, 5, 5, 7, 5, 9, 8, 9, 3, 4, 2, 9, 7, 3, 3, 7, 2, 6, 2, 5, 6, 5, 3, 1, 0, 8, 5, 6, 5, 7, 7, 5, 9, 4, 8, 9, 7, 8, 5, 5, 2, 1, 8, 5, 7, 5, 8, 9, 9, 3, 9, 3, 4, 5, 5, 1, 7, 0, 1, 2, 6, 5, 8, 7, 6, 7, 3, 7, 1, 2, 4, 6, 6, 5, 8, 8, 8, 1, 7, 6, 0, 4, 7, 7, 3, 4, 1, 0, 3, 8, 8, 9, 1, 9, 0, 8, 1, 7, 0

Offset

0,1

Links

Table of n, a(n) for n=0..99.

Example

x=0.3555759893429733726256531085657759489...

Mathematica

Plot[{1/x, Cos[x], 2 Cos[x], 3*Cos[x], 4 Cos[x]}, {x, 0, 2 Pi}]
t = x /. FindRoot[1/x == Cos[x], {x, .1, 5}, WorkingPrecision -> 100]
RealDigits[t]  (* A133868 *)
t = x /. FindRoot[1/x == 2 Cos[x], {x, .5, .7}, WorkingPrecision -> 100]
RealDigits[t]  (* A196603 *)
t = x /. FindRoot[1/x == 3 Cos[x], {x, .3, .4}, WorkingPrecision -> 100]
RealDigits[t]  (* A196604 *)
t = x /. FindRoot[1/x == 4 Cos[x], {x, .1, .3}, WorkingPrecision -> 100]
RealDigits[t]  (* A196605 *)
t = x /. FindRoot[1/x == 5 Cos[x], {x, .15, .23}, WorkingPrecision -> 100]
RealDigits[t]  (* A196606 *)
t = x /. FindRoot[1/x == 6 Cos[x], {x, .1, .2}, WorkingPrecision -> 100]
RealDigits[t]  (* A196607 *)

Crossrefs

Sequence in context: A365677 A335138 A343691 * A131506 A113722 A141791

Adjacent sequences: A196601 A196602 A196603 * A196605 A196606 A196607

Keyword

nonn,cons

Author

Clark Kimberling, Oct 04 2011

Status

approved