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%I A341944 #9 Feb 27 2021 15:03:33
%S A341944 3,4,7,6,9,8,15,12,11,18,13,14,17,16,31,24,19,20,23,22,37,26,25,28,27,
%T A341944 34,29,30,33,32,63,48,35,36,39,38,41,40,47,44,43,74,45,46,53,50,49,56,
%U A341944 51,52,55,54,69,58,57,60,59,66,61,62,65,64,127,96,67,68
%N A341944 Next larger integer with same number of runs in binary expansion as n.
%C A341944 Number of runs in binary expansion is given by A005811.
%C A341944 This is a permutation of A107907.
%H A341944 Rémy Sigrist, Table of n, a(n) for n = 1..8191
%H A341944 Index entries for sequences related to binary expansion of n
%F A341944 A005811(a(n)) = A005811(n).
%F A341944 a(2^k-1) = 2^(k+1)-1 for any k > 0.
%e A341944 The first terms in decimal and in binary, alongside A005811(n), are:
%e A341944 n a(n) bin(n) bin(a(n)) A005811(n)
%e A341944 -- ---- ------ --------- ----------
%e A341944 1 3 1 11 1
%e A341944 2 4 10 100 2
%e A341944 3 7 11 111 1
%e A341944 4 6 100 110 2
%e A341944 5 9 101 1001 3
%e A341944 6 8 110 1000 2
%e A341944 7 15 111 1111 1
%e A341944 8 12 1000 1100 2
%e A341944 9 11 1001 1011 3
%e A341944 10 18 1010 10010 4
%e A341944 11 13 1011 1101 3
%e A341944 12 14 1100 1110 2
%o A341944 (PARI) a(n) = my (r=hammingweight(bitxor(n, n>>1))); for (k=n+1, oo, if (r==hammingweight(bitxor(k, k>>1)), return (k)))
%o A341944 (Python)
%o A341944 def runs(n): return bin(n^(n>>1)).count('1')
%o A341944 def a(n):
%o A341944 nruns, m = runs(n), n + 1
%o A341944 while runs(m) != nruns: m += 1
%o A341944 return m
%o A341944 print([a(n) for n in range(1, 67)]) # _Michael S. Branicky_, Feb 24 2021
%Y A341944 Cf. A000975, A005811, A057168, A107907.
%K A341944 nonn,base
%O A341944 1,1
%A A341944 _Rémy Sigrist_, Feb 24 2021
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