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A360147 Primes in base 10 that are also prime when read in a smaller base that is one plus the largest digit in the prime in base 10.

%I A360147 #43 Jan 30 2023 08:25:24
%S A360147 2,3,5,7,11,13,23,31,37,43,61,73,101,103,107,113,131,151,223,227,233,
%T A360147 241,251,277,307,311,331,337,373,401,461,463,467,521,547,557,577,661,
%U A360147 673,701,827,887,1013,1033,1103,1151,1181,1213,1223,1231,1301,1327,1567
%N A360147 Primes in base 10 that are also prime when read in a smaller base that is one plus the largest digit in the prime in base 10.
%H A360147 Michael S. Branicky, <a href="/A360147/b360147.txt">Table of n, a(n) for n = 1..10000</a>
%p A360147 q:= n-> isprime(n) and (l-> (d-> d<9 and isprime(add(l[i]*
%p A360147    (d+1)^(i-1), i=1..nops(l))))(max(l)))(convert(n, base, 10)):
%p A360147 select(q, [$1..2000])[];  # _Alois P. Heinz_, Jan 27 2023
%t A360147 q[p_] := Module[{d = IntegerDigits[p], b}, b = Max[d] + 1; b <= 9 && PrimeQ[FromDigits[d, b]]]; Select[Prime[Range[250]], q] (* _Amiram Eldar_, Jan 27 2023 *)
%o A360147 (Python)
%o A360147 from sympy import isprime
%o A360147 def ok(n):
%o A360147     if not isprime(n): return False
%o A360147     s = str(n)
%o A360147     b = int(max(s)) + 1
%o A360147     return b != 10 and isprime(int(s, b))
%o A360147 print([k for k in range(1600) if ok(k)]) # _Michael S. Branicky_, Jan 27 2023
%o A360147 (PARI) isok(p)=if(isprime(p), my(v=digits(p), b=vecmax(v)+1); b<10 && isprime(fromdigits(v,b)), 0) \\ _Andrew Howroyd_, Jan 27 2023
%Y A360147 Subsequence of A038617.
%K A360147 nonn,base
%O A360147 1,1
%A A360147 _Alfred Jacob Mohan_, Jan 27 2023
%E A360147 More terms from _Michael S. Branicky_, Jan 27 2023