A159277 Ways to write the identity as a product of n 3-cycles in symmetric group S_4.
1, 0, 8, 32, 384, 2560, 22528, 172032, 1409024, 11141120, 89653248, 715128832, 5729419264, 45801799680, 366548615168, 2931852050432, 23456963887104, 187647121162240, 1501211329036288, 12009553193336832, 96076975302508544
Offset: 0
Links
- Flavien Mabilat, Some counting formulas for λ-quiddities over the rings Z / 2^m Z, arXiv:2402.09968 [math.CO], 2024.
Crossrefs
Cf. A091904.
Formula
a(n+1) = (2/3)*(-1)^n*((-8)^n-4^n).
O.g.f.: 1 - 8*x^2/(32*x^2+4*x-1).
a(n) = 8 * A091904(n-1). - R. J. Mathar, Jun 28 2009
Extensions
Offset corrected by R. J. Mathar, Jun 28 2009
Offset changed back and a(0) = 1 prepended by Andrey Zabolotskiy, Feb 21 2024