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 A272768 Greatest prime number with prime(n) prime digits. 2
 73, 773, 77773, 7777753, 77777777573, 7777777777573, 77777777777775557, 7777777777777777577, 77777777777777777775353, 77777777777777777777777775737, 7777777777777777777777777777333, 7777777777777777777777777777777773553, 77777777777777777777777777777777777777323 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Pierre CAMI, Table of n, a(n) for n = 1..125 MATHEMATICA 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 *) PROG (PARI) isok(n) = {if (isprime(n), vd = vecsort(digits(n), , 8); for (i=1, #vd, if (!isprime(vd[i]), return (0))); return (1); ); } a(n) = {gp = 7*(10^prime(n)-1)/9; while (!isok(gp), gp = precprime(gp-2)); gp; } \\ Michel Marcus, May 06 2016 CROSSREFS Cf. A264917, A272796. Sequence in context: A137835 A063784 A066101 * A100412 A169830 A197341 Adjacent sequences:  A272765 A272766 A272767 * A272769 A272770 A272771 KEYWORD nonn,base AUTHOR Pierre CAMI, May 06 2016 EXTENSIONS More terms from Michel Marcus, May 06 2016 a(57) in the b-file corrected by Giovanni Resta, May 06 2016 STATUS approved

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Last modified December 1 20:41 EST 2021. Contains 349435 sequences. (Running on oeis4.)