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A167170
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a(6)=14, for n>=7, a(n)=a(n-1)+gcd(n, a(n-1))
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8
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14, 21, 22, 23, 24, 25, 26, 39, 40, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 87, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 177, 180, 181, 182, 189, 190, 195
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OFFSET
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6,1
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COMMENTS
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For every n>=7, a(n)-a(n-1) is 1 or prime. This Rowland-like "generator of primes" is different from A106108 (see comment to A167168)
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REFERENCES
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E. S. Rowland, A natural prime-generating recurrence , Journal of Integer Sequences, Vol.11(2008), Article 08.2.8
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LINKS
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Table of n, a(n) for n=6..65.
V. Shevelev, A new generator of primes based on the Rowland idea
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MAPLE
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A167170 := proc(n) option remember; if n = 6 then 14; else procname(n-1)+igcd(n, procname(n-1)) ; end if; end proc: seq(A167170(i), i=6..80) ; [From R. J. Mathar, Oct 30 2010]
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CROSSREFS
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Cf. A167168 A106108 A132199 A167054 A167053 A166944 A166945 A116533 A163961 A163963 A084662 A084663 A134162 A135506 A135508 A118679 A120293
Sequence in context: A070719 A030643 A028395 * A213536 A133185 A013629
Adjacent sequences: A167167 A167168 A167169 * A167171 A167172 A167173
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KEYWORD
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nonn
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AUTHOR
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Vladimir Shevelev, Oct 29 2009, Nov 06 2009
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EXTENSIONS
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Terms > 91 from R. J. Mathar, Oct 30 2010
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STATUS
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approved
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