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A131852
Imaginary part of the function z defined in A131851.
13
0, 0, 1, 1, 0, 0, 1, 1, -1, -1, 0, 0, -1, -1, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, -1, -1, 0, 0, -1, -1, 0, 0, 1, 1, 2, 2, 1, 1, 2, 2, 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 2, 2, 1, 1, 2, 2, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, -1, -1, 0, 0, -1, -1, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, -1, -1, 0, 0, -1, -1, 0, 0, 1, 1, 2, 2, 1, 1, 2, 2, 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 2, 2, 1, 1, 2, 2, 0
OFFSET
0,35
COMMENTS
a(A000079(n)) = A056594(n+3);
a(A131855(n)) = 0; a(A131862(n)) > 0; a(A131857(n)) = 1; a(A131864(n)) < 0;
for n > 0: a(A098704(n+1)) = n and abs(a(m)) < n for m < A098704(n+1).
LINKS
MATHEMATICA
z[0] = 0; z[n_] := z[n] = z[Floor[n/2]]*I + Mod[n, 2]; Table[z[n] // Im, {n, 0, 120}] (* Jean-François Alcover, Mar 02 2019 *)
CROSSREFS
Sequence in context: A231734 A231735 A016429 * A139352 A214039 A089679
KEYWORD
sign
AUTHOR
Reinhard Zumkeller, Jul 22 2007
STATUS
approved