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A154315
Numbers k such that the number of prime digits in prime(k) equals the number of even digits in prime(k).
0
1, 5, 8, 10, 14, 15, 19, 23, 27, 28, 38, 39, 43, 46, 47, 50, 56, 61, 70, 77, 83, 85, 92, 97, 100, 104, 112, 113, 115, 120, 126, 127, 135, 136, 143, 144, 146, 149, 155, 156, 157, 158, 161, 163, 166, 167, 170, 173, 175, 177, 183, 184, 185, 189, 192, 195, 201, 208
OFFSET
1,2
MAPLE
From R. J. Mathar, May 01 2010: (Start)
noPrimDgs := proc(n) a := 0 ; for d in convert(n, base, 10) do if d in {2, 3, 5, 7} then a := a+1 ; end if; end do; a ; end proc:
noEvDgs := proc(n) a := 0 ; for d in convert(n, base, 10) do if type(d , 'even') then a := a+1 ; end if; end do; a ; end proc:
for n from 1 to 300 do p := ithprime(n) ; if noPrimDgs(p) = noEvDgs(p) then printf("%d, ", n) ; end if; end do: (End)
CROSSREFS
Sequence in context: A205676 A352676 A098594 * A182084 A262707 A257046
KEYWORD
nonn,base,less
AUTHOR
EXTENSIONS
Corrected(8, 23 inserted, 26 replaced by 27, 29 by 28, 97 inserted ...) by R. J. Mathar, May 01 2010
STATUS
approved