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%I #7 Aug 04 2015 13:57:45
%S 0,0,0,1,0,1,2,2,2,2,20,14,12,14,20,80,80,80,80,80,80,840,720,648,624,
%T 648,720,840
%N Triangle read by rows: T(n,k) = number of overlaps formed by element 1 in the set of permutations of n elements, where the element n does not occupy the k-th place after 1.
%D A. Sade, Sur les Chevauchements des Permutations, published by the author, Marseille, 1949.
%H Albert Sade, <a href="/A000108/a000108_17.pdf">Sur les Chevauchements des Permutations</a>, published by the author, Marseille, 1949. [Annotated scanned copy]
%e Triangle begins:
%e 0,
%e 0,0,
%e 1,0,1,
%e 2,2,2,2,
%e 20,14,12,14,20,
%e 80,80,80,80,80,80,
%e 840,720,648,624,648,720,840,
%e ...
%Y Row sums are A259705.
%K nonn,tabl,more
%O 2,7
%A _N. J. A. Sloane_, Jul 05 2015