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%I #16 Sep 08 2015 06:49:36
%S 47,71,2039,2437,108863,33487,4497359,1355840309,1979339339,
%T 6774006887,2081628860747539,122311273757,6525460043032393259,
%U 927920056668659,1429175974256442233,4928397730238375565449,5228233855704101657
%N Largest right-truncatable prime number in base n if 1 is considered as a prime (written in base 10).
%H Max Alekseyev, <a href="/A094335/b094335.txt">Table of n, a(n) for n = 2..75</a>
%H I. O. Angell, and H. J. Godwin, <a href="http://dx.doi.org/10.1090/S0025-5718-1977-0427213-2">On Truncatable Primes</a>, Math. Comput. 31, 265-267, 1977.
%H Domingo Gómez-Pérez, Alina Ostafe, Min Sha, <a href="http://arxiv.org/abs/1509.01936">The Arithmetic of Consecutive Polynomial Sequences over Finite Fields</a>, arXiv:1509.01936 [math.NT], 2015.
%H A. J. van der Poorten, <a href="http://dx.doi.org/10.1007/BF03023515">A quote</a>, Math. Intelligencer 7(2) (1985), 40.
%H <a href="/index/Tri#tprime">Index entries for sequences related to truncatable primes</a>
%e Example for n=10: 1,19,197,1979,19793,197933,1979339,19793393,197933933 and 1979339339 are all prime numbers.
%o (PARI) a(n) = my(S,m,D); D=select(x->(gcd(x,n)==1),vector(n-1,j,j)); S=concat([1],select(ispseudoprime,vector(n,j,j))); while(#S, m=vecmax(S); S=concat(vector(#D,j,select(ispseudoprime,vector(#S,i,S[i]*n+D[j]))));); m /* _Max Alekseyev_, Dec 06 2014 */
%Y Cf. A023107 (where 1 is not considered to be prime).
%K base,nonn
%O 2,1
%A _Martin Raab_, Jun 04 2004