cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A196610 Decimal expansion of the number c for which the curve y = c*cos(x) is tangent to the curve y = 1/x, and 0 < x < 2*Pi.

Original entry on oeis.org

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

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Author

Clark Kimberling, Oct 04 2011

Keywords

Examples

			c=1.7822251402031333124075510326661600195134426369...
		

Crossrefs

Programs

  • Mathematica
    Plot[{1/x, (1.78222) Cos[x]}, {x, .7, 1}]
    xt = x /. FindRoot[x == Cot[x], {x, .8, 1}, WorkingPrecision -> 100]
    c = N[Csc[xt]/xt^2, 100]
    RealDigits[c]      (* A196610 *)
    slope = -c*Sin[xt]
    RealDigits[slope]  (* A196611 *)