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 A039954 Palindromic primes formed from the reflected decimal expansion of Pi. 8
 3, 313, 31415926535897932384626433833462648323979853562951413 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Carlos Rivera reports that the next two members of this sequence have 301 and 921 digits. The first has been tested with APRTE-CLE. The second one is only a StrongPseudoPrime at the moment. - May 16 2003 Thomas Spahni reports that the fifth member of this sequence with 921 digits is prime. He used Francois Morain's ECPP-V6.4.5a which proved primality in 14913.7 seconds running on a Celeron Core2 CPU at 2.00GHz. - Jun 05 2008 Primes in A135697. Terms with an odd number of digits are the primes in A135698. - Omar E. Pol, Mar 06 2012 LINKS C. K. Caldwell, Prime Curios, 31414...51413 (53-digits) Eric Weisstein's World of Mathematics, Palindromic Prime. MATHEMATICA Select[Table[p = Flatten[RealDigits[Pi, 10, d]]; (FromDigits[p] - 1)*10^(Length[p] - 3) + FromDigits[Drop[Reverse[p], 2]], {d, 27}], PrimeQ] (* Arkadiusz Wesolowski, Dec 18 2011 *) CROSSREFS Cf. A002385, A119351. Sequence in context: A083974 A135698 A088102 * A134215 A034994 A139541 Adjacent sequences:  A039951 A039952 A039953 * A039955 A039956 A039957 KEYWORD base,nonn,bref AUTHOR STATUS approved

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Last modified January 22 22:38 EST 2018. Contains 298093 sequences.