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A355005 Table read by rows. T(n, k) = n*((k + n)!)^2/((k + n)*(n!)^2*k!) for n > 0 and T(0, 0) = 1. 1

%I #6 Jun 15 2022 11:52:52

%S 1,1,2,1,6,36,1,12,120,1200,1,20,300,4200,58800,1,30,630,11760,211680,

%T 3810240,1,42,1176,28224,635040,13970880,307359360,1,56,2016,60480,

%U 1663200,43908480,1141620480,29682132480,1,72,3240,118800,3920400,122316480,3710266560,111307996800,3339239904000

%N Table read by rows. T(n, k) = n*((k + n)!)^2/((k + n)*(n!)^2*k!) for n > 0 and T(0, 0) = 1.

%F T(n, k) = Lah(k + n, n), where Lah denotes the unsigned Lah numbers A271703.

%e [0] 1;

%e [1] 1, 2;

%e [2] 1, 6, 36;

%e [3] 1, 12, 120, 1200;

%e [4] 1, 20, 300, 4200, 58800;

%e [5] 1, 30, 630, 11760, 211680, 3810240;

%e [6] 1, 42, 1176, 28224, 635040, 13970880, 307359360;

%e [7] 1, 56, 2016, 60480, 1663200, 43908480, 1141620480, 29682132480;

%p T := (n, k) -> ifelse(n = 0, 1, n*((k + n)!)^2 / ((k + n)*(n!)^2*k!)):

%p seq(seq(T(n, k), k = 0..n), n = 0..8);

%Y T(n, 1) = A002378, T(n, n) = A187535, A355004 (row sums), A271703 (Lah).

%K nonn,tabl

%O 0,3

%A _Peter Luschny_, Jun 15 2022

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Last modified September 16 04:06 EDT 2024. Contains 375959 sequences. (Running on oeis4.)