Triangle read by rows: number of idempotents of rank k in partial Brauer monoid PB_n.

Terms

a(0) =1a(1) =1a(2) =1a(3) =4a(4) =2a(5) =1a(6) =16a(7) =18a(8) =3a(9) =1a(10) =100a(11) =88a(12) =48a(13) =4a(14) =1a(15) =676a(16) =860a(17) =280a(18) =100a(19) =5a(20) =1a(21) =5776a(22) =6696a(23) =4020a(24) =680a(25) =180a(26) =6a(27) =1a(28) =53824a(29) =76552