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%I M2966 #27 Jul 11 2023 12:22:07
%S 3,13,51413,951413,2951413,53562951413,979853562951413
%N Primes in A092845 (decimal expansion of Pi written backwards).
%C Next term is probably A092845(711), a 712-digit probable prime (Baillie-Pomerance-Selfridge-Wagstaff test, cf. PARI/GP documentation) beginning 2116599102453... and ending ...62648323979853562951413.
%C a(8) = A092845(711) is now a proven prime. - _Sean A. Irvine_, Jan 07 2018
%D M. Gardner, Whys and Wherefores, Univ. Chicago Press, 1989, p. 84.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H <a href="/index/Ph#Pi314">Index entries for sequences related to the number Pi</a>
%H Sean A. Irvine, <a href="/A007523/a007523.txt">Primo certificate for primality of a(8)</a>
%F Equals A000040 intersect A092845.
%e 51413 is in the list because it is prime and its decimal reversal, 31415, is the first 5 digits of Pi.
%t Module[{nn=1000,rd},d=RealDigits[Pi,10,nn][[1]];Select[Table[FromDigits[Reverse[Take[d,n]]],{n,nn}],PrimeQ]] (* _Harvey P. Dale_, Jul 11 2023 *)
%Y Cf. A005042, A092845, A011545.
%K base,nonn
%O 1,1
%A _N. J. A. Sloane_ and _Robert G. Wilson v_
%E Edited by _M. F. Hasler_ and _N. J. A. Sloane_, Mar 30 2008
%E Edited by _T. D. Noe_, Oct 30 2008
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