Triangle read by rows: T(n, k) is the number of graphs obtained by adding k pierced circles to a path graph P_n.

A354127

Triangle read by rows: T(n, k) is the number of graphs obtained by adding k pierced circles to a path graph P_n.

Terms

    a(0) =1a(1) =1a(2) =0a(3) =2a(4) =2a(5) =0a(6) =12a(7) =10a(8) =3a(9) =0a(10) =82a(11) =82a(12) =28a(13) =4a(14) =0a(15) =646a(16) =738a(17) =315a(18) =60a(19) =5a(20) =0a(21) =5574a(22) =7198a(23) =3636a(24) =900a(25) =110a(26) =6a(27) =0a(28) =51386a(29) =74086

External references