A221960 Triangle read by rows giving coefficients of polynomials arising in enumeration of multigraphs.

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

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 A325111

Adjacent sequences: A221957 A221958 A221959 * A221961 A221962 A221963

Keyword

sign,tabf,more

Author

N. J. A. Sloane, Feb 04 2013

Status

approved