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%I #13 Jan 26 2023 15:07:31
%S 2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,
%T 97,173,179,271,277,373,379,479,571,577,673,677,773,877,971,977,1777,
%U 2777,3779,5779,6779,8779,27773,27779,47777,47779,57773,67777,77773,97771
%N Primes with either no internal digits or all internal digits are 7.
%Y Cf. A069675, A069676, A069677, A069678, A069679, A069680, A069681, A069683, A069684.
%K nonn,base
%O 1,1
%A _Amarnath Murthy_, Apr 06 2002
%E Corrected by _Ray Chandler_, Nov 24 2003
%E Offset corrected and name changed by _Arkadiusz Wesolowski_, Sep 07 2011