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A245743 Primes p such that p - d is also prime, where d is the largest digit of p.

%I A245743 #18 Sep 08 2022 08:46:09
%S A245743 41,163,181,263,401,443,463,487,563,613,653,1021,1381,1433,1613,1663,
%T A245743 1831,2141,2243,2281,2441,2663,2851,2887,3041,3463,3613,3623,3643,
%U A245743 4133,4363,4463,4603,4643,4663,4801,5281,5563,5581,5653,5821,5851,5857,6043,6053
%N A245743 Primes p such that p - d is also prime, where d is the largest digit of p.
%C A245743 The least significant digit of a(n) is either 1, 3 or 7. - _Colin Barker_, Aug 03 2014
%C A245743 The largest digit of a(n) is 2, 4, 6 or 8. - _Robert Israel_, Aug 03 2014
%H A245743 Jens Kruse Andersen, <a href="/A245743/b245743.txt">Table of n, a(n) for n = 1..10000</a>
%e A245743 263 is in the sequence because 263 - 6 = 257, which is prime.
%p A245743 filter:= n -> isprime(n) and isprime(n - max(convert(n,base,10))):
%p A245743 select(filter, [$1..10^5]); # _Robert Israel_, Aug 03 2014
%o A245743 (PARI) select(p->isprime(p-vecsort(digits(p),,4)[1]), primes(2000))
%o A245743 (Magma) [p: p in PrimesUpTo(7000) | IsPrime(p-d) where d is Max(Intseq(p))]; // _Bruno Berselli_, Jul 31 2014
%Y A245743 Cf. A245742, A245744, A245745.
%K A245743 nonn,base
%O A245743 1,1
%A A245743 _Colin Barker_, Jul 31 2014