1620265923

Appears in sequences

• E.g.f.: (3+2*sqrt(3)*exp(x/2)*sin(sqrt(3)*x/2))/(exp(-x)+2*exp(x/2)*cos(sqrt(3)*x/2)).at n=16A178963
• Number of permutations of [n] with exactly five occurrences of the consecutive step pattern up, down, down.at n=0A246250
• The number of 3-alternating permutations of [n].at n=16A249402
• Number of linear extensions of a poset whose Hasse diagram consists of n binary shrubs with type E_n joins.at n=5A293952