Number of vertices of the n-th multiplihedron.

Terms

a(0) =0a(1) =1a(2) =2a(3) =6a(4) =21a(5) =80a(6) =322a(7) =1348a(8) =5814a(9) =25674a(10) =115566a(11) =528528a(12) =2449746a(13) =11485068a(14) =54377288a(15) =259663576a(16) =1249249981a(17) =6049846848a(18) =29469261934a(19) =144293491564a(20) =709806846980