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A127123 Triangle read by rows: T(n,k) = number of endofunctions on n points with k points in the image. 0

%I

%S 1,1,2,1,3,3,1,6,7,5,1,7,18,14,7,1,10,33,49,26,11,1,11,52,110,109,45,

%T 15,1,14,75,221,314,229,75,22,1,15,105,372,746,788,438,120,30,1,18,

%U 136,601,1508,2222,1797,806,187,42,1,19,174,888,2763,5208,5888,3806,1404,284,56

%N Triangle read by rows: T(n,k) = number of endofunctions on n points with k points in the image.

%e For n = 3, the 7 endofunctions are (1,2,3) -> (1,1,1), (1,1,2), (1,2,1), (2,1,1), (1,2,3), (1,3,2) and (2,3,1). The number of points in the image are respectively 1,2,2,2,3,3,3, so row 3 is 1,3,3.

%e The triangle starts:

%e 1

%e 1 2

%e 1 3 3

%e 1 6 7 5

%e 1 7 18 14 7

%K nonn,tabl

%O 1,3

%A _Franklin T. Adams-Watters_, with additional values from Christian Bower, Jan 05 2007

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Last modified August 10 14:50 EDT 2020. Contains 336381 sequences. (Running on oeis4.)