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A053585
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If n = p_1^e_1 * ... * p_k^e_k, p_1 < ... < p_k primes, then a(n) = p_k^e_k.
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28
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1, 2, 3, 4, 5, 3, 7, 8, 9, 5, 11, 3, 13, 7, 5, 16, 17, 9, 19, 5, 7, 11, 23, 3, 25, 13, 27, 7, 29, 5, 31, 32, 11, 17, 7, 9, 37, 19, 13, 5, 41, 7, 43, 11, 5, 23, 47, 3, 49, 25, 17, 13, 53, 27, 11, 7, 19, 29, 59, 5, 61, 31, 7, 64, 13, 11, 67, 17, 23, 7, 71, 9, 73, 37, 25, 19, 11, 13, 79
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OFFSET
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1,2
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COMMENTS
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Let p be the largest prime dividing n, a(n) is the largest power of p dividing n.
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LINKS
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FORMULA
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EXAMPLE
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a(42)=7 because 42=2*3*7, a(144)=9 because 144=16*9=2^4*3^2.
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MAPLE
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a:= n-> `if`(n=1, 1, (i->i[1]^i[2])(sort(ifactors(n)[2])[-1])):
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MATHEMATICA
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PROG
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(Haskell)
(Python)
from sympy import factorint, primefactors
def a(n):
if n==1: return 1
p = primefactors(n)[-1]
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CROSSREFS
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KEYWORD
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nonn,easy,nice
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AUTHOR
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Frederick Magata (frederick.magata(AT)uni-muenster.de), Jan 19 2000
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EXTENSIONS
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More terms from Andrew Gacek (andrew(AT)dgi.net), Apr 20 2000
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STATUS
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approved
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