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%I #9 Oct 04 2013 07:44:22
%S 1,1,1,1,1,1,1,1,1,1,1,1,11,66,286,1001,3003,8008,19448,43758,92378,
%T 184756,3711916,39277446,290971966,1693270006,8237327526,34822561201,
%U 131333661601,450356465701,1424215551901,4199713947571,122741742741301,1863639732429616
%N Number of 10 up, 10 down permutations of [n].
%H Alois P. Heinz, <a href="/A229891/b229891.txt">Table of n, a(n) for n = 0..200</a>
%p b:= proc(u, o, t) option remember; `if`(u+o=0, 1, add(`if`(t=10,
%p b(o-j, u+j-1, 1), b(u+j-1, o-j, t+1)), j=1..o))
%p end:
%p a:= n-> b(0, n, 0):
%p seq(a(n), n=0..35);
%Y Column k=10 of A229892.
%K nonn,eigen
%O 0,13
%A _Alois P. Heinz_, Oct 02 2013
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