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A088726
Smallest numbers having exactly n divisors d>1 such that also d+1 is a divisor.
9
1, 6, 12, 72, 60, 180, 360, 420, 840, 1260, 3780, 2520, 5040, 13860, 36960, 41580, 27720, 55440, 83160, 166320, 277200, 491400, 471240, 360360, 1113840, 720720, 1081080, 3341520, 2162160, 2827440, 5405400, 4324320, 12972960, 6126120
OFFSET
0,2
COMMENTS
A088722(a(n))=n, A088722(k)<>n, for n<a(n).
LINKS
FORMULA
a(n) = 2*A130317(n+1) for n>0. - Chandler
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Oct 12 2003
EXTENSIONS
Extended by Ray Chandler, May 29 2008
STATUS
approved