A178556 Primes with exactly seven 7's.

77767777, 77777177, 77777377, 77777747, 137777777, 172777777, 177677777, 177776777, 177777377, 177777577, 177777727, 177777773, 177777779, 177797777, 197777777, 272777777, 277177777, 277727777, 277771777, 277775777, 277777177

Offset

1,1

Links

Table of n, a(n) for n=1..21.

Mathematica

Select[Prime[Range[45*10^5, 152*10^5]], DigitCount[#, 10, 7]==7&] (* Harvey P. Dale, Dec 20 2022 *)

Crossrefs

Cf. A038618, A178550-5, A178557-8

Sequence in context: A295479 A203825 A109178 * A251174 A053431 A179578

Adjacent sequences: A178553 A178554 A178555 * A178557 A178558 A178559

Keyword

nonn,base

Author

Lekraj Beedassy, May 29 2010

Status

approved