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Nonpositive values in A317050, in order of appearance and negated.
3

%I #9 Oct 20 2020 19:01:22

%S 0,1,2,4,3,5,6,10,9,7,8,16,15,17,18,14,13,11,12,20,19,21,22,26,25,23,

%T 24,40,39,41,42,38,37,35,36,28,27,29,30,34,33,31,32,64,63,65,66,62,61,

%U 59,60,68,67,69,70,74,73,71,72,56,55,57,58,54,53,51,52,44

%N Nonpositive values in A317050, in order of appearance and negated.

%C This sequence is a permutation of the nonnegative integers, with inverse A338254 (the offset has been set to 0 so as to have a permutation).

%H Rémy Sigrist, <a href="/A338252/b338252.txt">Table of n, a(n) for n = 0..10922</a>

%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>

%F a(n) = -A317050(A053754(n+1)) for any n >= 0.

%F a(n) = n iff n belongs to A136324.

%e A338251 = 0, 1, -1, -2, 2, 3, 5, 4, -4, -3, -5, -6, -10, -9, -7, -8, ...

%e We keep: 0, 1, 2, 4, 3, 5, 6, 10, 9, 7, 8, ...

%o (PARI) A317050(n) = fromdigits(binary(bitxor(n, n>>1)), -2)

%o print (-select(v -> v<=0, apply(A317050, [0..152])))

%Y Cf. A053754, A136324, A317050, A338251, A338254.

%K nonn,look,base

%O 0,3

%A _Rémy Sigrist_, Oct 18 2020