

A211074


Decimal expansion of 4/Pi  1/2.


1



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
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OFFSET

0,1


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.


LINKS

Ivan Panchenko, Table of n, a(n) for n = 0..1000
Author?, Infinite 2D square grid of 1ohm resistors, April 30 2004 (this date is on an old archive.org copy).
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), 486492.
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:condmat/9909120 [condmat.meshall], 19992000.
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, Dec 12 2007.
Michael Pusateri, Google Labs Aptitude Test, Sep 13 2004.
xkcd, Nerd Sniping


EXAMPLE

0.77323954473516268615107010698011489627567716592365158998133875247117...


MATHEMATICA

RealDigits[4/Pi  1/2, 10, 87][[1]]


PROG

(PARI) 4/Pi1/2


CROSSREFS

Cf. A088538.
Sequence in context: A136141 A264806 A197843 * A204067 A291364 A244256
Adjacent sequences: A211071 A211072 A211073 * A211075 A211076 A211077


KEYWORD

nonn,cons


AUTHOR

Charles R Greathouse IV, May 02 2012


EXTENSIONS

Mathematica program modified by Harvey P. Dale, Jan 14 2015


STATUS

approved



