OFFSET
1,1
COMMENTS
Odd digits are 1, 3, 5, 7 or 9.
LINKS
Indranil Ghosh, Table of n, a(n) for n = 1..50000
FORMULA
a(n) ~ n log n. On the Riemann hypothesis, a(n) = ali(n) + O(n^k log n) where ali is the inverse logarithmic integral and k = log 5/log 10 = 0.69897.... - Charles R Greathouse IV, Apr 08 2016
MATHEMATICA
checkQ[n_] := Module[{d = IntegerDigits[n]}, Length[Select[d, OddQ]] != 2]; Select[Prime[Range[200]], checkQ] (* T. D. Noe, Jun 06 2012 *)
PROG
(PARI) is(n)=#select(d->d%2, digits(n))!=2 && isprime(n) \\ Charles R Greathouse IV, Apr 08 2016
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Juri-Stepan Gerasimov, Feb 15 2009
EXTENSIONS
183 replaced by 283 - R. J. Mathar, Feb 20 2009
Definition clarified by Jonathan Sondow, Jun 06 2012
STATUS
approved