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%I #8 Sep 17 2016 12:38:46
%S 1,2,3,4,5,6,7,8,9,10,23,11,20,13,22,15,26,17,24,19,25,14,27,16,29,18,
%T 35,12,37,21,34,55,28,31,40,33,41,30,47,32,45,38,49,36,59,42,53,44,39,
%U 46,51,43,50,61,48,65,71,52,63,58,67,54,73,56,79,60,77
%N a(n) = 1, a(n+1) = smallest number not occurring earlier, having with a(n) neither a common digit nor a common divisor.
%H Reinhard Zumkeller, <a href="/A239664/b239664.txt">Table of n, a(n) for n = 1..10000</a>
%o (Haskell)
%o import Data.List (delete, intersect); import Data.Function (on)
%o a239664 n = a239664_list !! (n-1)
%o a239664_list = 1 : f 1 [2..] where
%o f v ws = g ws where
%o g (x:xs) = if gcd v x == 1 && ((intersect `on` show) v x == "")
%o then x : f x (delete x ws) else g xs
%o (PARI) {u=[]; a=1; for(n=1,99, print1(a","); u=setunion(u,[a]); while(#u>1&&u[2]==u[1]+1,u=u[^1]); for(k=u[1]+1,9e9, setsearch(u,k)&&next;gcd(k,a)>1&&next; #setintersect(Set(digits(a)),Set(digits(k)))&&next; a=k; next(2)));a} \\ _M. F. Hasler_, Sep 17 2016
%Y Cf. A054659, A067581, A276633, A276512.
%K nonn,base
%O 1,2
%A _Reinhard Zumkeller_, Mar 23 2014
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