A131656 - OEIS

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A131656

Principal number of K. Saito for tree of type E_n.

-1, 3, 0, 3, 5, 18, 66, 298, 1511, 8670, 55168, 386394, 2951673, 24428654, 217723390, 2079109386, 21177620171, 229195610430, 2626388037372, 31768201320634, 404485298533085, 5407570127090958, 75736453324821754, 1108952444876609898, 16943545270848408495

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,2

LINKS

Table of n, a(n) for n=0..24.

Y. Sano, The principal numbers of K. Saito for the types A_l, D_l and E_l, Discr. Math., 307 (2007), 2636-2642.

CROSSREFS

Same as A131611 except for leading terms. Cf. A000111, A131281, A034428.

Sequence in context: A229704 A372865 A014715 * A194492 A194136 A194480

Adjacent sequences: A131653 A131654 A131655 * A131657 A131658 A131659

KEYWORD

sign

AUTHOR

N. J. A. Sloane, Oct 30 2007

STATUS

approved