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A091219
Moebius-analog for the domain GF(2)[X]: a(n)=0 if A091221(n)!=A091222(n) (i.e., if the polynomial is not squarefree), otherwise (-1)^A091222(n).
9
1, -1, -1, 0, 0, 1, -1, 0, 1, 0, -1, 0, -1, 1, 0, 0, 0, -1, -1, 0, 0, 1, 1, 0, -1, 1, 0, 0, 1, 0, -1, 0, 1, 0, 1, 0, -1, 1, 0, 0, -1, 0, 1, 0, 0, -1, -1, 0, 1, 1, 0, 0, 1, 0, -1, 0, 0, -1, -1, 0, -1, 1, 0, 0, 0, -1, -1, 0, 0, -1, 1, 0, -1, 1, 0, 0, 1, 0, 1, 0, 0, 1, -1, 0, 0, -1, -1, 0, 1, 0
OFFSET
1,1
COMMENTS
The absolute values give a characteristic function for squarefree GF(2)[X]-polynomials.
CROSSREFS
a(n) = A008683(A091203(n)) = A008683(A091205(n)).
Sequence in context: A266623 A359579 A246142 * A304109 A275601 A281011
KEYWORD
sign
AUTHOR
Antti Karttunen, Jan 03 2004
STATUS
approved