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Search: id:A136355
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| A136355 |
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Numbers of the form P = product of the first k odd primes where P+2 is composite. |
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+0
3
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| 1155, 255255, 4849845, 111546435, 152125131763605, 6541380665835015, 16294579238595022365, 58644190679703485491635, 3929160775540133527939545, 278970415063349480483707695, 20364840299624512075310661735
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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This sequence is different from A070826 and A118750
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EXAMPLE
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a(1)=1155 because 1157 is not prime.
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MATHEMATICA
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Contribution from Farideh Firoozbakht (mymontain(AT)yahoo.com), Aug 12 2009: (Start)
v=Select[Range[20], !PrimeQ[Product[Prime[k+1], {k, #}]+2]&]; Table[Product[Prime
[k+1], {k, v[[t]]}], {t, Length[v]}] (End)
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CROSSREFS
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Cf. A136349-A136354 A136356-A136358 A070826 A118750.
Sequence in context: A147577 A088012 A046406 this_sequence A157168 A062915 A034979
Adjacent sequences: A136352 A136353 A136354 this_sequence A136356 A136357 A136358
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KEYWORD
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easy,nonn
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AUTHOR
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Enoch Haga (Enokh(AT)comcast.net), Dec 25 2007
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EXTENSIONS
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Edited with more terms by Farideh Firoozbakht (mymontain(AT)yahoo.com), Aug 12 2009
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