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%I #14 Dec 10 2015 04:14:28
%S 1,1,2,4,0,0,2,6,2,0,8,4,4,8,6,2,28,20,32,12,12,8,16,6,106,80,156,120,
%T 132,48,48,8,32,16,352,396,708,696,1044,624,684,240,240,8,58,36,1174,
%U 1654,3698,3716,6396,5832,6756,3936,4176,1440,1440,8,98,80,3752
%N Triangle read by rows: T(n,k) (n>=0, k>=0) is the number of permutations of n and convexity k.
%C The convexity of a permutation in one-line notation is the maximal value of twice an entry minus the sum of its neighbors.
%C The row lengths are 2n-2 starting for n>=3.
%C Row sums give A000142.
%H FindStat - Combinatorial Statistic Finder, <a href="http://www.findstat.org/StatisticsDatabase/St000226">The convexity of a permutation</a>.
%e Triangle begins:
%e 1
%e 1
%e 2
%e 4 0 0 2
%e 6 2 0 8 4 4
%e 8 6 2 28 20 32 12 12
%e 8 16 6 106 80 156 120 132 48 48
%e ...
%Y Cf. A000142.
%K nonn,tabf
%O 0,3
%A _Christian Stump_, Oct 26 2015
%E More terms from _Alois P. Heinz_, Oct 26 2015
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