OFFSET
0,5
COMMENTS
Number of linear extensions in L(eps Z_n) that have an odd number of descents. (See Petersen and Yan Zhuang, p. 6.)
LINKS
T. Kyle Petersen and Yan Zhuang, Zig-zag Eulerian polynomials, arXiv:2403.07181 [math.CO], 2024.
MAPLE
enum := L -> ListTools:-Enumerate(L):
seq(add(c[2]*(1-irem(c[1], 2)), c = enum([A205497row(n)])), n = 0..25);
CROSSREFS
KEYWORD
nonn
AUTHOR
Peter Luschny, Jun 16 2024
STATUS
approved