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.

A248181 Decimal expansion of Sum_{h >= 0} 1/binomial(h, floor(h/2)).

Original entry on oeis.org

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

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Author

Clark Kimberling, Oct 04 2014

Keywords

Comments

Is this 2 + A248897? [Bruno Berselli, Mar 06 2015]. Yes, see Mathematica program below. - Vaclav Kotesovec, Jul 01 2024

Examples

			3.20919957615614523372938550509477048818...
Equals  1 + 1 + 1/2 + 1/3 + 1/6 + 1/10 + 1/20 + 1/35 + 1/70 + 1/126 + ...
		

Crossrefs

Cf. A248182.

Programs

  • Mathematica
    r = N[Sum[1/Binomial[h, Floor[h/2]], {h, 0, 2000}], 200];
    u = RealDigits[N[r, 200]][[1]]
    (* or *)
    Sum[1/Binomial[h, h/2], {h, 0, Infinity, 2}] + Sum[1/Binomial[h, (h-1)/2], {h, 1, Infinity, 2}] // Simplify // Expand (* Vaclav Kotesovec, Jul 01 2024 *)

Formula

Equals 2 + 2*Pi/3^(3/2). - Vaclav Kotesovec, Jul 01 2024