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%I #11 Dec 31 2019 16:58:40
%S 2,41,163,181,211,431,463,613,653,853,1163,1381,1483,1613,1801,1861,
%T 1873,2011,2063,2141,2221,2243,2411,2633,2851,3041,3181,3583,3623,
%U 4211,4241,4363,4421,4463,4483,4603,5563,5581,5821,5851,6113,6143,6203,6553
%N Primes which when multiplied by their largest digit and 1 is subtracted form another prime.
%H Harvey P. Dale, <a href="/A090195/b090195.txt">Table of n, a(n) for n = 1..1000</a>
%F In the prime sequence, select largest digit in each prime, multiply by the prime containing that digit, then subtract 1. If the result is another prime, add to sequence.
%e a(2)=41. Largest digit is 4. Multiply 41*4=164. 164-1=163, prime.
%t Select[Prime[Range[1000]],PrimeQ[# Max[IntegerDigits[#]]-1]&] (* _Harvey P. Dale_, Dec 31 2019 *)
%o (PARI) isok(p) = isprime(p) && isprime(p*vecmax(digits(p))-1); \\ _Michel Marcus_, Jun 08 2014
%Y Cf. A060418.
%K easy,nonn,base
%O 1,1
%A _Enoch Haga_, Jan 22 2004
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