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 A259704 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. 1

%I

%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.

%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

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Last modified December 3 17:23 EST 2021. Contains 349467 sequences. (Running on oeis4.)