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A007523 Primes in A092845 (decimal expansion of Pi written backwards).
(Formerly M2966)

%I M2966

%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.

%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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Last modified August 14 19:47 EDT 2020. Contains 336483 sequences. (Running on oeis4.)