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A082287
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a(1) = 1; for n>1, n appears omega(n) times, where omega(n)=A001221(n) is the number of distinct prime factors of n, a(1)=1.
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2
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1, 2, 3, 4, 5, 6, 6, 7, 8, 9, 10, 10, 11, 12, 12, 13, 14, 14, 15, 15, 16, 17, 18, 18, 19, 20, 20, 21, 21, 22, 22, 23, 24, 24, 25, 26, 26, 27, 28, 28, 29, 30, 30, 30, 31, 32, 33, 33, 34, 34, 35, 35, 36, 36, 37, 38, 38, 39, 39, 40, 40, 41, 42, 42, 42, 43, 44, 44, 45, 45, 46, 46, 47
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OFFSET
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1,2
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COMMENTS
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A027748(n) divides a(n) and a(n)=A027748(n) iff a(n) is prime; a(A013939(n)+1)=n.
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LINKS
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Table of n, a(n) for n=1..73.
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FORMULA
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a(n) is the least k such that sum_{p<=k}floor(k/p)>=n where p runs through the primes. [From Benoit Cloitre, Nov 08 2009]
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PROG
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(PARI) a(n)=if(n<0, 0, t=1; while(sum(k=1, t, floor(t/prime(k)))<n, t++); t) [From Benoit Cloitre, Nov 08 2009]
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CROSSREFS
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Cf. A082288.
Sequence in context: A195918 A176842 A099848 * A210062 A006164 A053758
Adjacent sequences: A082284 A082285 A082286 * A082288 A082289 A082290
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KEYWORD
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nonn
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AUTHOR
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Reinhard Zumkeller, Apr 07 2003
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STATUS
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approved
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