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%I #16 Apr 15 2023 08:24:23
%S 0,-1,1,-2,-5,-3,2,3,5,-4,-9,-7,-10,-21,-19,-6,-13,-11,4,7,9,6,11,13,
%T 10,19,21,-8,-17,-15,-18,-37,-35,-14,-29,-27,-20,-41,-39,-42,-85,-83,
%U -38,-77,-75,-12,-25,-23,-26,-53,-51,-22,-45,-43,8,15,17,14,27,29
%N a(n) = A328749(A362089(n)).
%C Every integer appears once in the sequence.
%H Rémy Sigrist, <a href="/A362090/b362090.txt">Table of n, a(n) for n = 0..6561</a>
%e For n = 5, the base-3 expansion of 5 is "12", so the base-3 expansion of A362089(5) is "102", and a(5) = -2^2 + 2^0 = -3.
%o (PARI) a(n) = { if (n==0, 0, n%3, 4*a(n\3) + (-1)^(n%3), 2*a(n/3)); }
%o (Python)
%o from gmpy2 import digits
%o def A362090(n): return sum((-(1<<i) if int(j)&1 else 1<<i) for i, j in enumerate(digits(n,3).replace('1','01').replace('2','02')[::-1]) if j!='0') # _Chai Wah Wu_, Apr 12 2023
%Y Cf. A328728, A328749, A362089.
%K sign,base
%O 0,4
%A _Rémy Sigrist_, Apr 08 2023