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A088427
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Number of primes in arithmetic progression starting with 23 and with d=2n.
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9
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1, 1, 2, 2, 1, 1, 2, 1, 3, 2, 1, 3, 1, 1, 4, 1, 1, 2, 2, 1, 1, 2, 1, 2, 2, 1, 1, 2, 1, 2, 1, 1, 2, 1, 1, 1, 2, 1, 4, 2, 1, 3, 2, 1, 2, 1, 1, 1, 1, 1, 1, 2, 1, 4, 1, 1, 3, 2, 1, 1, 1, 1, 2, 2, 1, 1, 2, 1, 1, 2, 1, 3, 1, 1, 2, 1, 1, 2, 2, 1, 1, 1, 1, 3, 2, 1, 2, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2
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OFFSET
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1,3
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COMMENTS
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Arithmetic progression is stopped when next term is not prime. E.g. for n=15 (d=30), a=3, that is 23,53,83,113 are prime, while next term, 143, is not prime.
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LINKS
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Table of n, a(n) for n=1..100.
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MATHEMATICA
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bb={}; Do[s=1; Do[If[PrimeQ[23+k*d], s=s+1, bb={bb, s}; Break[]], {k, 10}], {d, 2, 200, 2}]; Flatten[bb]
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CROSSREFS
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Cf. A088420, A088421, A088422, A088423, A088424, A088425, A088426, A088428, A088429.
Sequence in context: A116514 A124767 A112933 * A104482 A209332 A020945
Adjacent sequences: A088424 A088425 A088426 * A088428 A088429 A088430
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KEYWORD
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easy,nonn
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AUTHOR
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Zak Seidov, Sep 29 2003
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STATUS
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approved
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