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The H_3-Eulerian numbers.
1

%I #5 May 19 2016 04:13:23

%S 1,59,59,1

%N The H_3-Eulerian numbers.

%C a(n) is the number of elements of the Weyl group H_3 that have a descent set of size n.

%C Sum_{n=0..3} a(n) = 120, which is the order of the group H_3.

%D T. K. Petersen, Eulerian Numbers, Birkhauser, 2015, Table 11.5.

%Y Cf. A008292, A060187, A066094, A273000, A273035, A273036, A273181.

%K nonn,fini,full

%O 0,2

%A _Tom Edgar_, May 17 2016