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Search: id:A079615
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| A079615 |
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Product of all distinct prime factors of all composite numbers between n-th prime and next prime. |
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+0
1
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| 2, 6, 30, 6, 210, 6, 2310, 2730, 30, 39270, 7410, 42, 7590, 46410, 1272810, 30, 930930, 82110, 6, 21111090, 1230, 48969690, 1738215570, 2310, 102, 144690, 6, 85470, 29594505363092670, 16770, 49990710, 138, 7849357706190, 30
(list; graph; listen)
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OFFSET
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2,1
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COMMENT
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a(n) = A007947(A056831(n)), square-free kernel of least common multiple of composite numbers between n-th prime and next prime.
Note that each term is a product of distinct primes. - T. D. Noe, May 19 2007
Equals A076978 without its first term. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Sep 19 2008]
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LINKS
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T. D. Noe, Table of n, a(n) for n=2..1000
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EXAMPLE
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n=9: factorizations of numbers between 23=A000040(9) and 29=A000040(10) are 24=3*2^3, 25=5^2, 26=13*2 and 27=3^3, therefore a(9)=2*3*5*7*13=2730.
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CROSSREFS
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Cf. A005117, A002110.
Sequence in context: A088957 A030538 A076978 this_sequence A074168 A117213 A127797
Adjacent sequences: A079612 A079613 A079614 this_sequence A079616 A079617 A079618
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KEYWORD
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nonn,nice
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AUTHOR
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Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Jan 29 2003
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EXTENSIONS
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Corrected by T. D. Noe, May 19 2007
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