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A135689 a(i) = if [mod[i, 2] == 0 then a(i - 2) - (a(Floor[i/2]) - a(Abs[Floor[i/2] - 1])), otherwise a[i - 1] - (a(Abs[Floor[i/2] - 2)] - a(Abs[Floor[i/2] - 3]))]. 0
0, 1, -1, -2, 1, 2, 2, 1, -1, 1, -2, -1, -2, -5, -1, -2, 1, 1, -1, 0, 2, 4, 1, -1, 2, 5, 5, 4, 1, 2, 2, 5, -1, -5, -1, 0, 1, -2, 0, 0, -2, 0, -4, -5, -1, -3, 1, -1, -2, 1, -5, -3, -5, -8, -4, -7, -1, -1, -2, -1, -2, 1, -5, -6, 1, 1, 5, 2, 1, 7, 0, 4, -1, -5, 2, 1, 0, -1, 0, 3, 2, 0, 0, 0, 4, 6, 5, 3, 1, 5, 3, 4, -1, -5, 1, 3, 2, -2, -1, 1, 5 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

Recursion based on J. Mortensen's programming page for Per Nørgård's "infinite series" music composition sequence technique.

The composer Per Nørgård's name is also written in the OEIS as Per Noergaard.

LINKS

Table of n, a(n) for n=0..100.

J. Mortensen, Per Nørgård recursion programming

MATHEMATICA

p[0] = 0; p[1] = 1; p[2] = -1; p[3] = -2; p[i_] := p[i] = If[Mod[i, 2] == 0, p[i - 2] - (p[Floor[i/2]] - p[Abs[Floor[i/2] - 1]]), p[i - 1] - (p[Abs[Floor[i/2] - 2]] - p[Abs[Floor[i/2] - 3]])]; b = Table[p[n], {n, 0, 100}]

CROSSREFS

Sequence in context: A279362 A214841 A025917 * A029438 A304274 A081592

Adjacent sequences:  A135686 A135687 A135688 * A135690 A135691 A135692

KEYWORD

sign

AUTHOR

Roger L. Bagula, Feb 19 2008

EXTENSIONS

Edited by N. J. A. Sloane, Mar 03 2008

STATUS

approved

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Last modified July 21 06:55 EDT 2019. Contains 325192 sequences. (Running on oeis4.)