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A086780 Number of negative terms in n-th cyclotomic polynomial. 4
1, 0, 0, 0, 0, 1, 0, 0, 0, 2, 0, 1, 0, 3, 3, 0, 0, 1, 0, 2, 4, 5, 0, 1, 0, 6, 0, 3, 0, 3, 0, 0, 7, 8, 8, 1, 0, 9, 8, 2, 0, 4, 0, 5, 3, 11, 0, 1, 0, 2, 11, 6, 0, 1, 8, 3, 12, 14, 0, 3, 0, 15, 4, 0, 15, 7, 0, 8, 15, 8, 0, 1, 0, 18, 3, 9, 15, 8, 0, 2, 0, 20, 0, 4, 20, 21, 19, 5, 0, 3, 11, 11, 20, 23, 15, 1 (list; graph; refs; listen; history; internal format)
OFFSET

1,10

REFERENCES

See A051664

LINKS

T. D. Noe, Table of n, a(n) for n=1..1000

FORMULA

a(n) = 0 iff n is a prime power. - T. D. Noe (noe(AT)sspectra.com), Aug 08 2003

MATHEMATICA

Table[Count[CoefficientList[Cyclotomic[n, x], x], _?(#<0&)], {n, 0, 100}]

CROSSREFS

Cf. A086765, A000961.

Cf. A051664 (number of nonzero terms in n-th cyclotomic polynomial).

Sequence in context: A187495 A187496 A193056 * A158612 A143782 A073430

Adjacent sequences:  A086777 A086778 A086779 * A086781 A086782 A086783

KEYWORD

nonn

AUTHOR

Yuval Dekel (dekelyuval(AT)hotmail.com), Aug 03 2003

EXTENSIONS

More terms from T. D. Noe (noe(AT)sspectra.com), Aug 08 2003

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Last modified February 16 21:51 EST 2012. Contains 205978 sequences.