A107445 Number of 4n X 4n alternating-sign matrices of type UU.

1, 5, 198, 63206, 163170556, 3410501048325, 577465332522075000, 792313244775191409073200, 8810729389390415079342840510816

Offset

0,2

Links

Table of n, a(n) for n=0..8.

G. Kuperberg, Symmetry classes of alternating-sign matrices under one roof, arXiv:math/0008184 [math.CO], 2000-2001. [A_{UU}(4n)]

Formula

a(n) = A005156(n)*A059489(n).

Crossrefs

Cf. A005156, A059488, A059493.

Sequence in context: A080927 A211250 A208462 * A106990 A128791 A303136

Adjacent sequences: A107442 A107443 A107444 * A107446 A107447 A107448

Keyword

nonn,easy

Author

Paul Zinn-Justin, May 16 2007, Jun 04 2007

Status

approved