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A221960 Triangle read by rows giving coefficients of polynomials arising in enumeration of multigraphs. 0
1, 1, -1, 1, 0, -3, 2, 1, 0, 0, -4, -3, 12, -6, 1, 0, 0, 0, -5, -10, 20, 30, -60, 24, 1, 0, 0, 0, 0, -6, -15, 20, 120, -90, -270, 360, -120 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,6

LINKS

Table of n, a(n) for n=1..37.

Christian Brouder, William J. Keith, Ângela Mestre, Closed forms for a multigraph enumeration, arXiv preprint arXiv:1301.0874, 2013.

EXAMPLE

Triangle begins

1,

1, -1,

1, 0, -3, 2,

1, 0, 0, -4, -3, 12, -6,

1, 0, 0, 0, -5, -10, 20, 30, -60, 24,

1, 0, 0, 0, 0, -6, -15, 20, 120, -90, -270, 360, -120,

...

CROSSREFS

Sequence in context: A274537 A305234 A021761 * A171839 A257778 A242928

Adjacent sequences:  A221957 A221958 A221959 * A221961 A221962 A221963

KEYWORD

sign,tabf,more

AUTHOR

N. J. A. Sloane, Feb 04 2013

STATUS

approved

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Last modified September 23 14:40 EDT 2021. Contains 347618 sequences. (Running on oeis4.)