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A113279 Triangle T(n,k) of coefficients of r_1^n+r_2^n in terms of p and q, where r_1,r_2 are the roots of x^2+px+q=0. 1
2, -1, 1, -2, -1, 3, 1, -4, 2, -1, 5, -5, 1, -6, 9, -2, -1, 7, -14, 7, 1, -8, 20, -16, 2, -1, 9, -27, 30, -9, 1, -10, 35, -50, 25, -2, -1, 11, -44, 77, -55, 11, 1, -12, 54, -112, 105, -36, 2, -1, 13, -65, 156, -182, 91, -13, 1, -14, 77, -210, 294, -196, 49, -2, -1, 15, -90, 275, -450, 378, -140, 15 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

The triangle begins: 2 .-1 1..-2 .-1..3 1..-4.2

REFERENCES

M. Herkenhoff Konersmann, Sprokkel XXXI: x_1^n+x_2^n, Nieuw Tijdschr. Wisk, 42 (1954-55) 180.

LINKS

Table of n, a(n) for n=0..71.

FORMULA

T(n, k)=(-1)^(n+k)*A034807(n, k)

EXAMPLE

x_1^5+x_2^5 = -p^5 + 5p^3q - 5pq^2, so row 5 reads -1, 5, -5.

CROSSREFS

Sequence in context: A050221 A213235 * A213234 A034807 A182961 A135062

Adjacent sequences:  A113276 A113277 A113278 * A113280 A113281 A113282

KEYWORD

easy,sign,tabf

AUTHOR

Floor van Lamoen (fvlamoen(AT)hotmail.com), Oct 22 2005

STATUS

approved

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Last modified May 20 15:46 EDT 2013. Contains 225463 sequences.