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A238857 Array read by rows: row n lists total number of m-digit right-truncatable reversible primes in base n.

%I A238857 #17 Dec 24 2015 10:30:25
%S A238857 0,1,1,1,0,2,1,1,0,2,4,4,2,0,3,1,1,0,3,5,3,1,0,4,7,7,5,1,0,4,5,5,3,0,
%T A238857 4,5,6,1,0,4,8,7,9,4,1,0,5,5,7,5,0,5,10,8,4,1,1,0,6,11,17,12,3,1,0,6,
%U A238857 11,13,6,2,1,0,6,9,11,9,4,1,0,6,13,12,7,1,0,7,9,7,1,0
%N A238857 Array read by rows: row n lists total number of m-digit right-truncatable reversible primes in base n.
%C A238857 For definitions and more comments, see A238854 and A238850.
%C A238857 This is an irregular table with one line for every base, starting at 2, while the columns correspond to the number of digits (1,2,3,...). Each row terminates with a zero (in any given base there appears to be a finite number of instances).
%H A238857 Stanislav Sykora, <a href="/A238857/b238857.txt">Table of n, a(n) for n = 2..5071</a>
%H A238857 Stanislav Sykora, <a href="https://oeis.org/wiki/File:GeneticThreads.txt">PARI/GP scripts for genetic threads</a>, with code and comments.
%e A238857 These are the first rows of the table:
%e A238857    2: 0,
%e A238857    3: 1, 1, 1, 0,
%e A238857    4: 2, 1, 1, 0,
%e A238857    5: 2, 4, 4, 2, 0,
%e A238857    6: 3, 1, 1, 0,
%e A238857    7: 3, 5, 3, 1, 0,
%e A238857    8: 4, 7, 7, 5, 1, 0,
%e A238857    9: 4, 5, 5, 3, 0,
%e A238857   10: 4, 5, 6, 1, 0,
%e A238857   ...
%e A238857 Hence, there are 6 right truncatable reversible primes with 3 digits in base 10 (see A238850).
%o A238857 (PARI) See the link.
%Y A238857 Full in base 10: A238850, 16: A238851, 100: A238852, 256: A238853.
%Y A238857 In base n: A238854 (largest), A238855 (totals), A238856 (maximum digits).
%Y A238857 Cf. A007500, A023107, A024770, A237600, A237601, A237602.
%K A238857 nonn,tabf,base
%O A238857 2,6
%A A238857 _Stanislav Sykora_, Mar 13 2014