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A072500 Product of divisors of n which are >= n^(1/2). 16
1, 2, 3, 8, 5, 18, 7, 32, 27, 50, 11, 288, 13, 98, 75, 512, 17, 972, 19, 1000, 147, 242, 23, 13824, 125, 338, 243, 2744, 29, 27000, 31, 4096, 363, 578, 245, 419904, 37, 722, 507, 64000, 41, 86436, 43, 10648, 6075, 1058, 47, 1769472, 343, 12500, 867, 17576, 53 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
a(n) = n iff n is not a composite number.
LINKS
EXAMPLE
The divisors of 20 are 1, 2, 4, 5, 10 and 20. a(20) = 5*10*20= 1000.
MATHEMATICA
Table[Times @@ Select[Divisors[n], # >= Sqrt[n] &], {n, 1, 55}]
CROSSREFS
Sequence in context: A070935 A095164 A075384 * A208449 A346957 A062956
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Jul 20 2002
EXTENSIONS
Edited by Robert G. Wilson v, Jul 22 2002
Corrected a(16) by Harvey P. Dale, Oct 06 2011
STATUS
approved

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Last modified February 21 03:13 EST 2024. Contains 370219 sequences. (Running on oeis4.)