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A178556
Primes with exactly seven 7's.
5
77767777, 77777177, 77777377, 77777747, 137777777, 172777777, 177677777, 177776777, 177777377, 177777577, 177777727, 177777773, 177777779, 177797777, 197777777, 272777777, 277177777, 277727777, 277771777, 277775777, 277777177
OFFSET
1,1
MATHEMATICA
Select[Prime[Range[45*10^5, 152*10^5]], DigitCount[#, 10, 7]==7&] (* Harvey P. Dale, Dec 20 2022 *)
CROSSREFS
Sequence in context: A295479 A203825 A109178 * A251174 A053431 A179578
KEYWORD
nonn,base
AUTHOR
Lekraj Beedassy, May 29 2010
STATUS
approved