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A171073 Smallest positive integer a(n) not yet in the sequence and sharing no digit with n, (n-1) or (n+1) in its decimal representation. 0

%I

%S 3,4,1,2,7,8,5,6,22,23,9,40,50,20,27,24,25,26,33,34,35,44,10,11,13,14,

%T 15,16,17,45,46,47,18,12,19,21,29,41,51,28,36,5,56,60,30,31,32,52,37,

%U 38,39,48,61,62,70,42,43,63,71,72,49,54,57,77,73,80,53,100,111,58,59,64,65

%N Smallest positive integer a(n) not yet in the sequence and sharing no digit with n, (n-1) or (n+1) in its decimal representation.

%t f[s_List] := Block[{k = 1, len = Length@s}, id = Union@ Flatten[ IntegerDigits /@ {len, len + 1, len + 2}]; While[ MemberQ[s, k] || Intersection[id, IntegerDigits@k] != {}, k++ ]; Append[s, k]]; Nest[f, {}, 73] (* _Robert G. Wilson v_, Sep 25 2010 *)

%Y Cf. A171072. - _Robert G. Wilson v_, Sep 25 2010

%K nonn,base,fini

%O 1,1

%A _N. J. A. Sloane_, Sep 06 2010, based on an email from _Eric Angelini_, Jun 30 2010

%E a(22) inserted, a(25) and a(26) corrected, etc. by _Robert G. Wilson v_, Sep 25 2010

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Last modified July 25 23:39 EDT 2021. Contains 346294 sequences. (Running on oeis4.)