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The n-th term in the sequence is the minimal number that has some subset of DPS's that form an n-term arithmetic progression.
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%I #2 Oct 02 2013 16:23:32

%S 1,4,72,1008,36400

%N The n-th term in the sequence is the minimal number that has some subset of DPS's that form an n-term arithmetic progression.

%C Definition: m is a DPS (divisor pair sum) for n, if m = d + n/d where d | n, and d <= n/d.

%H C. Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_413.htm">Prime Puzzle 413: DPS in AP</a>

%e 72's solution: 3+24, 4+18, 8+9. The difference between terms is 5. (Note: 72 = 3*24 = 4*18 = 8*9)

%K hard,nonn

%O 1,2

%A _Fred Schneider_, Sep 08 2009