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Let a(1) = 4. For n > 1, a(n) is the least number greater than a(n-1) such that the Hamming distance D(a(n-1),a(n)) = 4.
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%I #14 Nov 07 2020 13:31:26

%S 4,11,16,31,35,44,49,62,70,73,82,93,97,110,112,127,143,145,158,162,

%T 173,176,191,199,200,211,220,224,239,241,254,286,290,301,304,319,327,

%U 328,339,348,352,367,369,382,398,400,415,419

%N Let a(1) = 4. For n > 1, a(n) is the least number greater than a(n-1) such that the Hamming distance D(a(n-1),a(n)) = 4.

%C All terms are odious (A000069).

%H Harvey P. Dale, <a href="/A207460/b207460.txt">Table of n, a(n) for n = 1..1000</a>

%t nxt[n_]:=Module[{k=n+1},While[HammingDistance[PadLeft[IntegerDigits[ n,2],IntegerLength[ k,2]],IntegerDigits[k,2]]!=4,k++];k]; NestList[ nxt,4,50] (* _Harvey P. Dale_, Nov 07 2020 *)

%Y Cf. A000225, A205509, A205510, A205511, A205302, 205649, A205533, A122565, A206852, A206853, A206960, A207016, A207017.

%K nonn,base

%O 1,1

%A _Vladimir Shevelev_, Feb 18 2012