A211074 Decimal expansion of 4/Pi - 1/2.

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

Offset: 0

Author

Charles R Greathouse IV, May 02 2012

Keywords

• nonn
• cons

Comments

Equivalent resistance between two nodes on an infinite rectangular lattice of ideal unit resistors, where the nodes are separated by two resistors along one axis and one resistor on the other.

Examples

			0.77323954473516268615107010698011489627567716592365158998133875247117...
		

Links

• Ivan Panchenko, Table of n, a(n) for n = 0..1000
• Author?, Infinite 2D square grid of 1-ohm resistors, April 30 2004.
• D. Atkinson and F. J. van Steenwijk, Infinite resistive lattices, Aug 14 1998.
• D. Atkinson and F. J. van Steenwijk, Infinite resistive lattices, Am. J. Phys. 67 (1999), 486-492.
• Matthew Beckler, Infinite Grid of Resistors - Solution by Simulation, Dec 16 2009.
• Kevin Brown, Infinite Grid of Resistors.
• J. Cserti, Application of the lattice Green's function for calculating the resistance of an infinite networks of resistors, arXiv:cond-mat/9909120 [cond-mat.mes-hall], 1999-2000.
• Peter G. Doyle and J. Laurie Snell, Random walks and electric networks (2006), section 1.1.4.
• Alan Eustace, Pencils down, people (official Google Blog article, archived on archive.org), Sep 30 2004.
• Randall Munroe, Nerd Sniping, xkcd Web Comic #356, Dec 12 2007.
• Michael Pusateri, Google Labs Aptitude Test, Sep 13 2004.
• Index entries for transcendental numbers

Crossrefs

Cf. A088538, A355565.

Programs

Mathematica

RealDigits[4/Pi - 1/2, 10, 87][[1]] (* modified by Harvey P. Dale, Jan 14 2015 *)

PARI

4/Pi-1/2