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A261018 First differences of A260273.

%I A261018 #14 Aug 02 2018 07:25:03
%S A261018 2,2,3,3,4,2,3,3,4,4,2,3,3,5,7,5,5,4,3,3,5,5,3,3,4,4,4,5,7,4,5,5,4,3,
%T A261018 3,5,5,3,3,6,8,3,3,4,4,7,4,4,5,5,5,7,7,4,5,9,5,4,4,4,3,3,3,6,3,3,6,9,
%U A261018 5,6,5,7,8,3,3,6,3,3,4,4,4,7,4,4,8,4,4,5,5
%N A261018 First differences of A260273.
%C A261018 a(n) = A261461(A260273(n)). - _Reinhard Zumkeller_, Aug 30 2015
%H A261018 N. J. A. Sloane, <a href="/A261018/b261018.txt">Table of n, a(n) for n = 1..19999</a>
%t A261018 b[1] = 1;
%t A261018 b[n_] := b[n] = Module[{bits, k}, bits = IntegerDigits[b[n-1], 2]; For[k = 1, True, k++, If[SequencePosition[bits, IntegerDigits[k, 2]] == {}, Return[b[n-1] + k]]]];
%t A261018 a[n_] := b[n+1] - b[n];
%t A261018 Array[a, 100] (* _Jean-François Alcover_, Aug 02 2018 *)
%o A261018 (Python)
%o A261018 A261018_list, a = [], 1
%o A261018 for i in range(10**3):
%o A261018     b, s = 1, format(a,'b')
%o A261018     while format(b,'b') in s:
%o A261018         b += 1
%o A261018     a += b
%o A261018     s = format(a,'b')
%o A261018     A261018_list.append(b) # _Chai Wah Wu_, Aug 26 2015
%o A261018 (Haskell)
%o A261018 a261018 n = a261018_list !! (n-1)
%o A261018 a261018_list = zipWith (-) (tail a260273_list) a260273_list
%o A261018 -- _Reinhard Zumkeller_, Aug 30 2015
%Y A261018 Cf. A260273.
%Y A261018 Cf. A261645, A261461.
%K A261018 nonn
%O A261018 1,1
%A A261018 _N. J. A. Sloane_, Aug 17 2015