Problem Contest – Problem of the Week – November 18, 2003
Triangular numbers and a related infinite series: Let 
be the nth triangular number. Consider the set of alternate triangular numbers {T2k-1} = {1,6,15,…}. Find the sum of their reciprocals.
Submit written solution with justification to John Emerson, Warner 312, before 3:00 on Friday, December 5. Or leave them in the Warner mailroom.
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