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A157450
a(n) = the n-th divisor of the smallest positive integer with exactly n^2 divisors.
0
1, 2, 3, 4, 6, 6, 9, 8, 10, 10, 24, 12, 32, 16, 18, 18, 64, 21, 81, 22, 28, 32, 144, 27, 40, 42, 36, 35, 288, 39, 384, 39, 56, 70, 63, 45, 729, 84, 75, 52, 1024, 56, 1296, 66, 66, 128, 1944, 60, 112, 78, 126, 88, 3072, 78, 140, 78, 150, 224, 5184, 81, 6144, 256, 104, 90
OFFSET
1,2
EXAMPLE
The smallest positive integer with 5^2 divisors = A061707(5) = 1296. The first 5 of the 25 divisors of 1296 are: 1,2,3,4,6. Since the 5th divisor is 6, then a(5) = 6.
CROSSREFS
Cf. A061707.
Sequence in context: A308162 A092404 A094871 * A195013 A079667 A073061
KEYWORD
nonn
AUTHOR
Leroy Quet, Mar 01 2009
EXTENSIONS
More terms from R. J. Mathar, Mar 14 2009
a(45)-a(64) from Ray Chandler, Jun 19 2009
STATUS
approved