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A209493
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Indices of primes in sequence A006190.
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3
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2, 5, 11, 17, 61, 103, 167, 193, 293, 643, 647, 911, 11243, 29437, 55021
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OFFSET
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1,1
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COMMENTS
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Index must be prime. The indices greater than 293 yield probable primes.
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LINKS
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Table of n, a(n) for n=1..15.
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MATHEMATICA
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seq=RecurrenceTable[{a[n]==3*a[n-1]+a[n-2], a[1]==1, a[2]==3}, a, {n, 1000}]; Select[Range[1000], PrimeQ[seq[[#]]]&]
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CROSSREFS
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Cf. A006190, A006497, A000129, A096650
Sequence in context: A038977 A141778 A191053 * A117877 A226215 A169745
Adjacent sequences: A209490 A209491 A209492 * A209494 A209495 A209496
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KEYWORD
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nonn,hard,more
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AUTHOR
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Vaclav Kotesovec, Mar 09 2012
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EXTENSIONS
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a(14)-a(15) from Vaclav Kotesovec, Sep 08 2013
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STATUS
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approved
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