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%I #25 May 14 2016 13:49:54
%S 73,773,77773,7777753,77777777573,7777777777573,77777777777775557,
%T 7777777777777777577,77777777777777777775353,
%U 77777777777777777777777775737,7777777777777777777777777777333,7777777777777777777777777777777773553,77777777777777777777777777777777777777323
%N Greatest prime number with prime(n) prime digits.
%H Pierre CAMI, <a href="/A272768/b272768.txt">Table of n, a(n) for n = 1..125</a>
%t a[n_] := Block[{p=7(10^Prime[n]-1)/9-1},While[{} != Intersection[ IntegerDigits@p, {0, 1, 4, 6, 8, 9}], p = NextPrime[p, -1]]; p]; Array[a, 13] (* _Giovanni Resta_, May 06 2016 *)
%o (PARI) isok(n) = {if (isprime(n), vd = vecsort(digits(n),,8); for (i=1, #vd, if (!isprime(vd[i]), return (0))); return (1););}
%o a(n) = {gp = 7*(10^prime(n)-1)/9; while (!isok(gp), gp = precprime(gp-2)); gp;} \\ _Michel Marcus_, May 06 2016
%Y Cf. A264917, A272796.
%K nonn,base
%O 1,1
%A _Pierre CAMI_, May 06 2016
%E More terms from _Michel Marcus_, May 06 2016
%E a(57) in the b-file corrected by _Giovanni Resta_, May 06 2016
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