Number of permutations of [n] having exactly three alternating descents.
A302896
Number of permutations of [n] having exactly three alternating descents.
Terms
- a(0) =5a(1) =26a(2) =182a(3) =1196a(4) =8699a(5) =67054a(6) =556952a(7) =4945368a(8) =46901985a(9) =473324450a(10) =5068610666a(11) =57423496708a(12) =686431008183
External references
- oeis: A302896