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 A106107 Primes with minimal digit = 7. 2
 7, 79, 97, 787, 797, 877, 887, 977, 997, 7789, 7877, 7879, 8779, 8887, 9787, 9887, 77797, 77899, 77977, 77999, 78779, 78787, 78797, 78877, 78887, 78889, 78977, 78979, 78989, 79777, 79889, 79979, 79987, 79997, 79999 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Robert Israel, Table of n, a(n) for n = 1..10000 MAPLE Res:= NULL: count:= 0: for d from 1 while count < 100 do   for m from 3^d to  2*3^d-1 while count < 100 do   L:= convert(m, base, 3)[1..d];   if min(L) <> 0 then next fi;   x:= add((L[i]+7)*10^(i-1), i=1..d);   if isprime(x) then count:= count+1; Res:= Res, x; fi od od: Res; # Robert Israel, Jan 07 2020 MATHEMATICA Select[Prime[Range[8000]], Min[IntegerDigits[ # ]]==7&] CROSSREFS Sequence in context: A106110 A082992 A261181 * A020471 A065902 A140613 Adjacent sequences:  A106104 A106105 A106106 * A106108 A106109 A106110 KEYWORD nonn,base AUTHOR Zak Seidov, May 07 2005 STATUS approved

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Last modified May 18 11:30 EDT 2021. Contains 343995 sequences. (Running on oeis4.)