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Search: id:A118144
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| A118144 |
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Numbers of prime factors of l, where l is defined in A118534. |
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+0
2
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| 0, 0, 1, 0, 2, 2, 2, 2, 1, 3, 2, 2, 2, 2, 1, 1, 2, 2, 3, 2, 1, 3, 2, 4, 2, 3, 3, 3, 3, 3, 2, 3, 4, 2, 3, 2, 1, 2, 2, 1, 2, 3, 4, 4, 3, 2, 1, 2, 4, 4, 1, 2
(list; graph; listen)
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OFFSET
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1,5
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COMMENT
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a(n) = 0 only for n = 1, 2 and 4.
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LINKS
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Remi Eismann, Table of n, a(n) for n = 1..10000
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FORMULA
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a(n) = numbers of factors of l, largest l such that prime(n+1) = prime(n) + (prime(n) mod l), or 0 if no such l exists.
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EXAMPLE
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For a(1), l=0 thus a(1)=0,
for a(3), l=3 thus a(3)=1,
for a(8), l=15=3*5 thus a(8)=2,
for a(24), l=81=3*3*3*3 thus a(24)=4.
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CROSSREFS
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Cf. A118534, A117563, A118123, A117078.
Sequence in context: A052435 A094701 A054715 this_sequence A136691 A064741 A114294
Adjacent sequences: A118141 A118142 A118143 this_sequence A118145 A118146 A118147
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KEYWORD
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nonn
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AUTHOR
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Remi Eismann & Fabien Sibenaler (reismann(AT)free.fr), May 14 2006, Feb 14 2008
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