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A141457
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Primes of the form ((3*x*y-y-6)/(3*x+1), where x=prime and y=composite.
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0
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61, 73, 181, 241, 421, 433, 577, 601, 829, 997, 1033, 1069, 1153, 1621, 1657, 1753, 1861, 2017, 2089, 2113, 2521, 2593, 2917, 3049, 3121, 3373, 3517, 3637, 3709, 3967, 4093, 4201, 4357, 4561, 4861, 5119, 5179, 5323, 5443, 5623
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OFFSET
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1,1
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COMMENTS
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x=p(i)=i-th primet and y=c(j)=j-th composite.
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LINKS
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Table of n, a(n) for n=1..40.
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EXAMPLE
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If x=11 and y=65, then
((3*11*65-65-6)/(3*11+1)=2074/34=61=a(1).
If x=13 and y=77, then ((3*13*77-77-6)/(3*13+1)=2820/40=73=a(2).
If x=31 and y=185, then ((3*31*185-185-6)/(3*31+1)=17014/94=181=a(3).
If x=41 and y=245, then ((3*41*245-245-6)/(3*41+1)=29884/124=241=a(4).
If x=71 and y=425, then ((3*71*425-425-6)/(3*71+1)=90094/214=421=a(5).
If x=73 and y=437, then ((3*73*437-437-6)/(3*73+1)=95260/220=433=a(6),
etc.
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CROSSREFS
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Cf. A002808, A000040.
Sequence in context: A139944 A179012 A033236 * A112998 A118162 A217076
Adjacent sequences: A141454 A141455 A141456 * A141458 A141459 A141460
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KEYWORD
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nonn
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AUTHOR
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Juri-Stepan Gerasimov, Aug 28 2008
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STATUS
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approved
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