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Triangle read by rows: number of permutation trees of power n and height <= n - k.
3

%I #4 Aug 04 2014 20:11:09

%S 1,1,2,1,6,5,1,24,23,9,1,120,119,68,14,1,720,719,517,152,20,1,5040,

%T 5039,4163,1581,292,27,1,40320,40319,36180,16776,3917,508,35,1,362880,

%U 362879,341733,186030,52029,8489,823,44,1

%N Triangle read by rows: number of permutation trees of power n and height <= n - k.

%C Partial row sums of A179454 starting from the diagonal. Special case: A179456(n,n-2) = A000096(n) for n > 1.

%H Peter Luschny, <a href="http://www.oeis.org/wiki/User:Peter_Luschny/PermutationTrees"> Permutation trees</a>.

%e 1,

%e 1,

%e 2, 1,

%e 6, 5, 1,

%e 24, 23, 9, 1,

%e 120, 119, 68, 14, 1,

%e 720, 719, 517, 152, 20, 1,

%e 5040, 5039, 4163, 1581, 292, 27, 1,

%e 40320, 40319, 36180, 16776, 3917, 508, 35, 1,

%e 362880, 362879, 341733, 186030, 52029, 8489, 823, 44, 1

%Y Cf. A179454, A179455.

%K nonn,tabf

%O 0,3

%A _Peter Luschny_, Aug 11 2010