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A028233
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If n = p_1^e_1 * ... * p_k^e_k, p_1 < ... < p_k primes, then a(n) = p_1^e_1.
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14
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1, 2, 3, 4, 5, 2, 7, 8, 9, 2, 11, 4, 13, 2, 3, 16, 17, 2, 19, 4, 3, 2, 23, 8, 25, 2, 27, 4, 29, 2, 31, 32, 3, 2, 5, 4, 37, 2, 3, 8, 41, 2, 43, 4, 9, 2, 47, 16, 49, 2, 3, 4, 53, 2, 5, 8, 3, 2, 59, 4, 61, 2, 9, 64, 5, 2, 67, 4, 3, 2, 71, 8, 73, 2, 3, 4, 7, 2, 79, 16, 81, 2, 83, 4, 5, 2
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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LINKS
| T. D. Noe, Table of n, a(n) for n=1..1000
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FORMULA
| a(n) = A020639(n)^A067029(n). - Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), May 13 2006
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MATHEMATICA
| a[n_] := Power @@ First[ FactorInteger[n]]; Table[a[n], {n, 1, 86}] (* From Jean-François Alcover, Dec 01 2011 *)
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PROG
| (Haskell)
a028233 1 = 1
a028233 n = f (n `div` p) p where
f x y | m > 0 = y
| otherwise = f x' (p*y) where (x', m) = divMod x p
p = a020639 n
-- Reinhard Zumkeller, Aug 17 2011
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CROSSREFS
| Cf. A020639, A006530, A034684, A028233, A034699, A053585.
See also A028234.
Sequence in context: A026362 A081811 A034684 * A066296 A162961 A145255
Adjacent sequences: A028230 A028231 A028232 * A028234 A028235 A028236
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KEYWORD
| nonn,nice,easy
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AUTHOR
| Marc LeBrun (mlb(AT)well.com)
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