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%I #19 Nov 03 2019 01:44:10
%S 7,35,77,91,119,133,175,315,357,371,399,511,539,553,595,735,777,791,
%T 917,931,959,973,1113,1155,1197,1337,1351,1379,1393,1519,1533,1575,
%U 1715,1757,1771,1799,1911,1939,1953,1995,3115,3157,3171,3199,3311,3339
%N Multiples of 7 containing only odd digits.
%H Robert Israel, <a href="/A061825/b061825.txt">Table of n, a(n) for n = 1..10000</a>
%H <a href="/index/Ar#10-automatic">Index entries for 10-automatic sequences</a>.
%e 315 = 7*45 is a term as it contains only odd digits.
%p R:= NULL:
%p for d from 1 to 4 do
%p for n from 5^d to 2*5^d-1 do
%p L:= map(t -> 2*t+1,convert(n,base,5)[1..d]);
%p x:= add(L[i]*10^(i-1),i=1..nops(L));
%p if x mod 7 = 0 then
%p R:= R, x;
%p fi;
%p od od:
%p R; # _Robert Israel_, Nov 02 2019
%t Select[7*Range[500], Count[IntegerDigits[#], _?EvenQ]==0&] (* _Harvey P. Dale_, Jun 13 2011 *)
%o (PARI) is(n)=n%7==0 && #setintersect(Set(digits(n)), [0,2,4,6,8])==0 \\ _Charles R Greathouse IV_, Feb 15 2017
%Y Subsequence of A008589.
%Y Cf. A061826.
%K nonn,base,easy
%O 1,1
%A _Amarnath Murthy_, May 28 2001
%E More terms from Larry Reeves (larryr(AT)acm.org), May 30 2001
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