A052253 - OEIS

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A052253

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

0

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

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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

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