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A154767
Primes with even largest digit.
4
2, 41, 43, 61, 83, 163, 181, 211, 241, 263, 281, 283, 383, 401, 421, 431, 433, 443, 461, 463, 487, 563, 587, 601, 613, 631, 641, 643, 653, 661, 683, 787, 811, 821, 823, 827, 853, 857, 863, 877, 881, 883, 887, 1021, 1061, 1063, 1087, 1163, 1181, 1187, 1201
OFFSET
1,1
COMMENTS
Relative density 0 in the primes. It is natural to conjecture that there are infinitely many, but can this be proved? - Charles R Greathouse IV, Nov 12 2010
LINKS
MAPLE
A054055 := proc(n) max( op(convert(n, base, 10))) ; end: isA154767 := proc(n) RETURN( isprime(n) and ( A054055(n) mod 2 ) = 0 ) ; end; for n from 1 to 400 do p := ithprime(n) ; if isA154767(p) then printf("%d, ", p) ; fi; od: # R. J. Mathar, Jan 18 2009
MATHEMATICA
fQ[p_] := EvenQ[ Sort[ IntegerDigits[ p]][[-1]]]; Select[ Prime@ Range@ 200, fQ] (* Robert G. Wilson v, May 15 2014 *)
Select[Prime[Range[200]], EvenQ[Max[IntegerDigits[#]]]&] (* Harvey P. Dale, Sep 21 2014 *)
CROSSREFS
Sequence in context: A033841 A107194 A235147 * A042923 A222717 A059698
KEYWORD
nonn,base
AUTHOR
EXTENSIONS
837 replaced by 827. R. J. Mathar, Jan 18 2009
STATUS
approved