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.

A212479 Decimal expansion of the absolute value of infinite power tower of i.

Original entry on oeis.org

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

Views

Author

Stanislav Sykora, May 17 2012

Keywords

Comments

This c = |z|, where z is the complex solution of z = i^z or, equivalently, z = i^i^i^...

Examples

			0.5675551633069578253846131441924533439 ...
		

Crossrefs

Cf. A077589 (real part of z), A077590 (imaginary part of z), A212480 (argument of z).

Programs

  • Mathematica
    2*I*ProductLog[-I*Pi/2]/Pi // Abs // N[#, 108]& // RealDigits[#][[1]]& (* Jean-François Alcover, Feb 05 2013 *)
  • PARI
    my(z="I"); for (i=1, 1000, z = concat(z, "^I")); z = eval(z); sqrt(norml2([real(z), imag(z)])) \\ Michel Marcus, May 12 2023

Formula

c = |i^i^i^...|.