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A123258
a(n) = n-th divisor of the smallest positive integer with at least n divisors.
1
1, 2, 4, 6, 6, 12, 12, 24, 36, 48, 30, 60, 30, 40, 60, 120, 90, 180, 120, 240, 90, 120, 180, 360, 120, 144, 180, 240, 360, 720, 420, 840, 315, 420, 630, 1260, 420, 560, 840, 1680, 315, 360, 420, 504, 630, 840, 1260, 2520, 360, 420, 504, 560, 630, 720, 840, 1008
OFFSET
1,2
COMMENTS
a(n) = n-th divisor of A061799(n).
EXAMPLE
The smallest positive integer with at least 11 divisors is 60, which has 12 divisors.
So a(11) = the 11th divisor of 60, which is 30.
MATHEMATICA
f[n_] := Block[{k = 1, d}, While[d = Divisors[k]; Length[d] < n, k++ ]; d[[n]]]; Table[f[n], {n, 60}] (* Ray Chandler, Nov 11 2006 *)
Do[k = 1; While[Length[Divisors[k]] < n, k++ ]; Print[Divisors[k][[n]]], {n, 100}] (* Ryan Propper, Nov 12 2006 *)
CROSSREFS
Cf. A061799.
Sequence in context: A141677 A087459 A285103 * A278227 A104968 A286894
KEYWORD
nonn
AUTHOR
Leroy Quet, Nov 06 2006
EXTENSIONS
Extended by Ray Chandler, Nov 11 2006
More terms from Ryan Propper, Nov 12 2006
STATUS
approved