A273035 The E_7-Eulerian numbers.

1, 17635, 309969, 1123915, 1123915, 309969, 17635, 1

Offset: 0

Author

Tom Edgar, May 13 2016

Keywords

• nonn
• fini
• full

Comments

a(n) is the number of elements of the Weyl group E_7 that have a descent set of size n.

Sum_{n=0..7} a(n) = 2903040, which is the order of the group E_7.

References

• T. K. Petersen, Eulerian Numbers, Birkhauser, 2015, Table 11.5.

Crossrefs

Cf. A008292, A060187, A066094, A273000.