An infinite net is made of identical wires. The resistance between points 1 and 2 is r, and the resistance between points 1 and 3 is R. Find the resistance R14 between points 1 and 4.

We received many solutions to our January Challenge, Lore of the rings. We are pleased to recognize the following successful solvers:

  • Salvatore Basile (Università degli Studi di Palermo, Palermo, Italy)

  • Philip Blanco (Grossmont College, El Cajon, CA)

  • Phil Cahill (The SI Organization, Inc., Rosemont, PA)

  • Don Easton (Lacombe, Alberta, Canada)

  • Arunangshu Karmakar, student (Salt Lake School, Kolkata, India)

  • Stephen McAndrew (Sydney, Australia)

  • Matthew W. Milligan (Farragut High School, Knoxville, TN)

  • Daniel Mixson (Naval Academy Preparatory School, Newport, RI)

  • Steven Morris (emeritus, Los Angeles Harbor College, Wilmington, CA)

  • Carl E. Mungan (U. S. Naval Academy, Annapolis, MD)

  • Pascal Renault (John Tyler Community College, Midlothian, VA)

  • Randall J. Scalise (Southern Methodist...

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