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A109305
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Primes containing as substring the string reversal of their index.
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1
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17, 491, 1823, 6883, 183661, 757063, 9642461, 10398683, 11948737, 61241363, 125644177, 141037697, 168598249, 329147719, 1507060573, 2936125141, 24257906011, 74038127803, 863209344623, 1167992076341
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OFFSET
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1,1
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COMMENTS
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a(21) > 2*10^12. [From Donovan Johnson, May 08 2010]
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LINKS
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Table of n, a(n) for n=1..20.
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EXAMPLE
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94th prime, 491, contains 49 = the string reversal of its index;
281st prime, 1823, contains 182 = the string reversal of its index;
7144652nd prime, 125644177, contains 2564417 = the string reversal of its index; etc.
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MATHEMATICA
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fQ[n_] := StringPosition[ ToString[ Prime[n]], StringReverse[ ToString[n]]] != {}; Do[ If[ fQ[n], Print[ Prime[n]]], {n, 10^8}] (* Robert G. Wilson v, Jun 28 2005 *)
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CROSSREFS
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Corresponding indices form A109304.
Sequence in context: A166116 A173148 A142368 * A130660 A185659 A012792
Adjacent sequences: A109302 A109303 A109304 * A109306 A109307 A109308
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KEYWORD
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base,nonn
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AUTHOR
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Zak Seidov, Jun 25 2005
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EXTENSIONS
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a(14)-a(16) from Robert G. Wilson v, Jun 28 2005
a(17)-a(20) from Donovan Johnson, May 08 2010
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STATUS
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approved
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