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A055356 Triangle of increasing mobiles (circular rooted trees) with n nodes and k leaves. 8
1, 1, 0, 1, 1, 0, 1, 4, 2, 0, 1, 11, 18, 6, 0, 1, 26, 98, 96, 24, 0, 1, 57, 424, 874, 600, 120, 0, 1, 120, 1614, 6040, 8244, 4320, 720, 0, 1, 247, 5682, 35458, 83500, 83628, 35280, 5040, 0, 1, 502, 19022, 187288, 701164, 1169768, 915984, 322560, 40320, 0, 1 (list; table; graph; refs; listen; history; internal format)
OFFSET

1,8

COMMENTS

In an increasing rooted tree, nodes are numbered and numbers increase as you move away from root.

This is also related to the solution of the equation df/dt=f e^f (see the Maple code). - Frederic Chapoton (fchapoton(AT)voila.fr), Jul 16 2004

LINKS

Index entries for sequences related to mobiles

EXAMPLE

1; 1,0; 1,1,0; 1,4,2,0; 1,11,18,6,0; ...

MAPLE

P[1]:=1; for n from 1 to 8 do P[n+1]:=simplify((1+n*x)*P[n]+x*diff(P[n], x)) end; (Chapoton)

CROSSREFS

Row sums give A029768. Columns 2 through 8: A000295, A055357-A055362.

Sequence in context: A088393 A121225 A049430 * A164789 A028956 A129681

Adjacent sequences:  A055353 A055354 A055355 * A055357 A055358 A055359

KEYWORD

nonn,tabl

AUTHOR

Christian G. Bower (bowerc(AT)usa.net), May 15 2000

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Last modified February 16 03:44 EST 2012. Contains 205860 sequences.