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%I #15 Dec 21 2015 03:18:48
%S 23,53,449,191,1171,30671,5827,3733,901687,10357,834469,3043427,
%T 5430889,4060019,498061,34763,118248433,62344463,218555173,4463351,
%U 114607657,7903613,14523874693,211675817,32814697,93375223,162466979,8052409793,12006877873
%N Largest right-truncatable, reversible prime in base n.
%C See A238850, A238851, A238852, A238853 for the finite lists of such numbers in four bases selected as examples. A sequence conceptually similar to this one, but for right-truncatable (not reversible!) primes is A023107. The present, more restrictive, condition leads to smaller numbers which can be evaluated in reasonable time for much higher n values.
%H Stanislav Sykora, <a href="/A238854/b238854.txt">Table of n, a(n) for n = 3..390</a>
%H Stanislav Sykora, <a href="https://oeis.org/wiki/File:GeneticThreads.txt">PARI/GP scripts for genetic threads</a>, with code and comments.
%e a(4) = 53 because it is a prime which in base 4 reads 311_b4, its reverse 113_b4 (decimal 23) is also a prime, the same holds for all its base-4 prefixes (31_b4 and 3_b4), and it is the largest natural having these properties.
%o (PARI) See the link.
%Y Cf. Full in base 10: A238850, 16: A238851, 100: A238852, 256: A238853.
%Y Cf. In base n: A238855 (totals), A238856 (maximum digits), A238857 (m-digits counts).
%Y Cf. A007500, A023107, A024770, A237600, A237601, A237602.
%K nonn,base,hard
%O 3,1
%A _Stanislav Sykora_, Mar 07 2014