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A098091
Graded dimension of the space of invariant bilinear forms on the free pre-Lie algebra on one generator.
2
1, 1, 4, 7, 17, 36, 88, 196, 481, 1148, 2838, 7020, 17708, 44837, 114971, 296457
OFFSET
5,3
COMMENTS
The sequence starts at index 5 because the previous terms vanish.
FORMULA
It seems that a(n+1) = A000081(n) - A051573(n). - Andrey Zabolotskiy, Aug 05 2024
CROSSREFS
This is related in some sense to A000081.
Sequence in context: A023860 A009881 A049944 * A319782 A374563 A057450
KEYWORD
nonn,more
AUTHOR
F. Chapoton, Sep 14 2004
STATUS
approved