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.

A333182 Decimal expansion of Sum_{k>=1} mu(k)^2 / 2^k.

Original entry on oeis.org

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

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Author

Ilya Gutkovskiy, Mar 10 2020

Keywords

Comments

Squarefree constant: binary expansion is the characteristic function of squarefree numbers (A008966).

Examples

			0.93137635638313358... = (0.1110111001...)_2.
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                            123 567 10
		

Crossrefs

Programs

  • Mathematica
    RealDigits[Sum[MoebiusMu[n]^2/2^n, {n, 1, 500}], 10, 100][[1]] (* Amiram Eldar, Jun 22 2020 *)

Formula

Equals Sum_{k>=1} mu(k)/(2^(k^2) - 1). - Amiram Eldar, Jun 22 2020