A052253 Triangle T(n,k) (n >= 1, k >= 1) giving filtration of bigrading of Hopf algebra of rooted trees.

1, 1, 1, 2, 1, 1, 3, 3, 2, 1, 8, 5, 4, 2, 1, 16, 13, 9, 6, 3, 1, 41, 28, 21, 13, 8, 3, 1, 98, 71, 49, 33, 20, 10, 4, 1, 250, 174, 121, 79, 50, 27, 13, 4, 1, 631, 445, 304, 201, 127, 74, 38, 16, 5, 1, 1646, 1137, 776, 510, 325, 192, 106, 49, 19, 5, 1, 4285, 2974

Offset

0,4

Links

Table of n, a(n) for n=0..67.

D. J. Broadhurst and D. Kreimer, Towards cohomology of renormalization...

Example

1; 1,1; 2,1,1; 3,3,2,1; 8,5,4,2,1; ...

Crossrefs

Cf. A052250.

Sequence in context: A363394 A368343 A131336 * A271453 A247749 A247367

Adjacent sequences: A052250 A052251 A052252 * A052254 A052255 A052256

Keyword

nonn,nice,tabl

Author

David Broadhurst, Feb 05 2000

Status

approved