[1] Find all positive integers that cannot be written as the sum of 2 or more consecutive positive integers.

[2] Find all integers that cannot be written as the sum of 2 or more consecutive integers.

[3] Find all positive integers that can only be written as the sum of 2 or more consecutive positive integers in one way.

(In reply to possible solution by Dej Mar)

Counterexample for your [3]
18 = 2^2 * 3 = 5+6+7 = 3+4+5+6

Steve already disproved your [2]

I agree with your [1].  (Proof?)

{yes 3,4,5 is not different than 5,4,3}

Posted by Jer on 2011-04-15 00:22:27