A161796 Primes with at least one digit appearing exactly five times in the decimal expansion.

101111, 111119, 111121, 111191, 111211, 111611, 112111, 113111, 131111, 199999, 311111, 313333, 323333, 331333, 333233, 333323, 333331, 333337, 333383, 333433, 333533, 334333, 343333, 353333, 444443, 444449, 511111, 555557, 599999, 611111

Offset: 1

Author

Ki Punches, Jun 19 2009

Keywords

• nonn
• base

Comments

The sequence is probably infinite.

Crossrefs

Cf. A105992, A161786.

Programs

Maple

isdgctm := proc(n,d) local dgs,a,i ; dgs := convert(n,base,10) ; a := [seq(0,j=0..9)] ;
for i in dgs do a := subsop(i+1=op(i+1,a)+1,a) ; od: if convert(a,set) intersect {d} <> {} then true; else false; fi; end:
for n from 1 to 100000 do p := ithprime(n) ; if isdgctm(p,5) then printf("%d,",p) ; fi; od: # R. J. Mathar, Jun 21 2009

Extensions

Edited and corrected by R. J. Mathar, Jun 21 2009