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%I #13 May 15 2018 14:12:31
%S 1,3,5,7,9,15,17,19,35,37,39,55,57,59,75,77,79,95,97,99,155,157,159,
%T 175,177,179,195,197,199,355,357,359,375,377,379,395,397,399,555,557,
%U 559,575,577,579,595,597,599,755,757,759,775,777,779,795,797,799,955,957,959,975,977,979,995,997,999,1555,1557,1559,1575,1577,1579
%N Numbers n such that n and 2n+1 use only odd decimal digits.
%C Sophie-Germain-analog for numbers with odd digits.
%C Also numbers with the first digit an odd digit and the other digits in {5, 7, 9}. - _David A. Corneth_, May 15 2018
%H Harvey P. Dale, <a href="/A238257/b238257.txt">Table of n, a(n) for n = 1..1000</a>
%F a(5(3^k-1)/2) = 10^k-1. - _Giovanni Resta_, Feb 22 2014
%t Select[Range[1600],AllTrue[Join[IntegerDigits[#],IntegerDigits[ 2#+1]], OddQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, May 15 2018 *)
%o (PARI) is(n)=#setminus(setunion(Set(digits(n)),Set(digits(2*n+1))), [1,3,5,7,9])==0 \\ _Charles R Greathouse IV_, May 15 2018
%Y Cf. A005384, A111153, A211162, A111173, A111176.
%K nonn,base,easy
%O 1,2
%A _Zak Seidov_, Feb 21 2014
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