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%I #12 Sep 30 2020 20:19:20
%S 23,41,43,47,67,89,157,197,199,317,337,409,461,641,683,773,937,971,
%T 991,1231,1303,1321,1453,1619,1789,1877,2003,2089,2113,2153,2203,2243,
%U 2311,2339,2351,2579,2683,2917,2971,2999,3019,3613,3709,4241,4261,4357,4481,4591,4603,4663,5059,5527,5741,6221
%N Primes p such that if the decimal representation of p is interpreted in base q, where q is the prime before p, the result is prime.
%C 3, 5 and 7 are not included because they are not legal digits in bases 2, 3 and 5.
%H Robert Israel, <a href="/A337871/b337871.txt">Table of n, a(n) for n = 1..10000</a>
%e a(3)=43 is included because 43 is prime, the previous prime is 41, and 43_41=167 is prime.
%p R:= NULL: count:= 0:
%p p:= 11:
%p while count < 100 do
%p q:= p; p:= nextprime(p);
%p L:= convert(p,base,10);
%p x:= add(L[i]*q^(i-1),i=1..nops(L));
%p if isprime(x) then count:= count+1; R:= R, p;
%p fi
%p od:
%p R;
%Y Cf. A337872.
%K nonn,base
%O 1,1
%A _J. M. Bergot_ and _Robert Israel_, Sep 27 2020
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