Problem Contest – Problem of the Week – November 4, 2003  

Integers of form 122…221 and their divisors: Let n be an integer with 5n+1 digits that begins and ends with 1s and has all 2s in between.  Show that n is always divisible by a sum of two squares.  (Hint: 41 = 42 + 52)

Submit your written solution with justification to John Emerson, Warner 312, before 3:00 on Tuesday, November 11.  Or leave them in the Warner mailroom.

Note:  Join us at the weekly seminars, usually on Tuesday at 3:00 for refreshments.