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%I #14 Dec 11 2022 23:04:49
%S 0,1,2,4,11,7,20,23,27,28,61,61,153,130,151,157,301,343,561,806,1046,
%T 615,1227,2136,2472,2288,3685,2110,5241,4798,7017,10630,14175,14127,
%U 21267,15034,24677,29289,46814,29291,63872,58451,82839,143678,196033,99103,218108
%N Total number of restricted right truncatable primes in base n.
%C Prime digits p in base n are counted if there is no prime with 2 digits which can have its rightmost digit removed to produce p.
%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 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/TruncatablePrime.html">Truncatable Prime</a>.
%H <a href="/index/Tri#tprime">Index entries for sequences related to truncatable primes</a>
%o (Python)
%o from sympy import isprime, primerange
%o def fromdigits(digs, base):
%o return sum(d*base**i for i, d in enumerate(digs))
%o def a(n):
%o prime_lists, an = [(p, ) for p in primerange(1, n)], 0
%o digits = 1
%o while len(prime_lists) > 0:
%o new_prime_strs = set()
%o for p in prime_lists:
%o can_extend = False
%o for d in range(n):
%o c = (d, ) + p
%o if isprime(fromdigits(c, n)):
%o can_extend = True
%o new_prime_strs.add(c)
%o if not can_extend:
%o an += 1
%o prime_lists = list(new_prime_strs)
%o digits += 1
%o return an
%o print([a(n) for n in range(2, 27)]) # _Michael S. Branicky_, Dec 11 2022
%Y Cf. A076586.
%K nonn
%O 2,3
%A _Martin Renner_, Jan 04 2008
%E a(6) corrected and a(11) and beyond from _Michael S. Branicky_, Dec 11 2022
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