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A108381 Number of distinct magnitudes of the nonzero sums of distinct n-th roots of unity. 2
1, 1, 1, 2, 3, 3, 8, 9, 16, 17, 62, 23, 186, 95, 280, 240, 1963, 225, 6830, 1091 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

There are 2^n sums of the n-th roots of unity.

LINKS

Table of n, a(n) for n=1..20.

T. D. Noe, Sums of Roots of Unity Plots

EXAMPLE

a(4)=2 because the nonzero sums of 4th roots of unity have magnitude 1 or sqrt(2).

CROSSREFS

Cf. A103314 (number of subsets of the n-th roots of unity summing to zero).

Sequence in context: A011155 A161136 A258163 * A238761 A261469 A292498

Adjacent sequences:  A108378 A108379 A108380 * A108382 A108383 A108384

KEYWORD

nonn

AUTHOR

T. D. Noe, Jun 01 2005

STATUS

approved

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Last modified October 17 04:09 EDT 2019. Contains 328106 sequences. (Running on oeis4.)