A109305 Primes containing as substring the string reversal of their index.

17, 491, 1823, 6883, 183661, 757063, 9642461, 10398683, 11948737, 61241363, 125644177, 141037697, 168598249, 329147719, 1507060573, 2936125141, 24257906011, 74038127803, 863209344623, 1167992076341

Offset

1,1

Comments

a(21) > 2*10^12. [From Donovan Johnson, May 08 2010]

Links

Table of n, a(n) for n=1..20.

Example

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.

Mathematica

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 *)

Crossrefs

Corresponding indices form A109304.

Sequence in context: A166116 A173148 A142368 * A130660 A185659 A012792

Adjacent sequences: A109302 A109303 A109304 * A109306 A109307 A109308

Keyword

base,nonn

Author

Zak Seidov, Jun 25 2005

Extensions

a(14)-a(16) from Robert G. Wilson v, Jun 28 2005

a(17)-a(20) from Donovan Johnson, May 08 2010

Status

approved