cp's OEIS Frontend

A256185 Second of two variations by Per Nørgård of his "infinity sequence", cf. A004718: v(0) = 0; v(3*n) = -v(n); v(3*n+1) = v(n) - 3; v(3*n+2) = -2 - v(n).

%I A256185 #6 Oct 06 2017 11:40:16
%S A256185 0,-3,-2,3,-6,1,2,-5,0,-3,0,-5,6,-9,4,-1,-2,-3,-2,-1,-4,5,-8,3,0,-3,
%T A256185 -2,3,-6,1,0,-3,-2,5,-8,3,-6,3,-8,9,-12,7,-4,1,-6,1,-4,-1,2,-5,0,3,-6,
%U A256185 1,2,-5,0,1,-4,-1,4,-7,2,-5,2,-7,8,-11,6,-3,0,-5,0
%N A256185 Second of two variations by Per Nørgård of his "infinity sequence", cf. A004718: v(0) = 0; v(3*n) = -v(n); v(3*n+1) = v(n) - 3; v(3*n+2) = -2 - v(n).
%C A256185 Per Nørgård's surname is also written as Noergaard;
%C A256185 for all odd j exists k such that abs(a(k+1)-a(k)) = j, in contrast to A004718, where this holds also for even j > 0, see link.
%D A256185 Yu Hin (Gary) Au, Christopher Drexler-Lemire, and Jeffrey Shallit, "Notes and note pairs in Norgard's infinity series", J. of Mathematics and Music (2017). DOI:  http://dx.doi.org/10.1080/17459737.2017.1299807
%H A256185 Reinhard Zumkeller, <a href="/A256185/b256185.txt">Table of n, a(n) for n = 0..10000</a>
%H A256185 Christopher Drexler-Lemire, Jeffrey Shallit, <a href="http://arxiv.org/abs/1402.3091">Notes and Note-Pairs in Noergaard's Infinity Series</a>, arXiv:1402.3091 [math.CO], page 13
%o A256185 (Haskell)
%o A256185 a256185 n = a256185_list !! n
%o A256185 a256185_list = 0 : concat (transpose [map (subtract 3) a256185_list,
%o A256185                                       map (-2 -) a256185_list,
%o A256185                                       map negate $ tail a256185_list])
%Y A256185 Cf. A004718, A256184, A087808, A085144, A255723.
%K A256185 sign
%O A256185 0,2
%A A256185 _Reinhard Zumkeller_, Mar 19 2015