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%I #15 Jan 27 2019 10:58:43
%S 1,1,2,1,3,6,1,4,12,24,1,5,20,60,120,1,6,30,120,360,720,1,7,42,210,
%T 840,2520,5040,1,8,56,336,1680,6720,20160,40320,1,9,72,504,3024,15120,
%U 60480,181440,362880,1,10,90,720,5040,30240,151200,604800,1814400,3628800
%N Triangle T(n,k) = n!/(n-k)! read by rows, 0 <= k < n.
%C Row n contains the same set of values as row A181512(n,.), which are related to labeled rooted trees (A000169) and Bell numbers (A000110) respectively.
%H Reinhard Zumkeller, <a href="/A181511/b181511.txt">Rows n = 0..100 of triangle, flattened</a>
%F T(n,k) = A008279(n,k). - _R. J. Mathar_, Mar 03 2011
%e The triangle begins:
%e 1;
%e 1, 2;
%e 1, 3, 6;
%e 1, 4, 12, 24;
%e which is A181512 without duplicates.
%p A181511 := proc(n,k) n!/(n-k)! ; end proc:
%p seq(seq(A181511(n,k),k=0..n-1),n=1..16) ; # _R. J. Mathar_, Mar 03 2011
%o (Haskell)
%o a181511 n k = a181511_tabl !! (n-1) !! k
%o a181511_row n = a181511_tabl !! (n-1)
%o a181511_tabl = tail $ map init a008279_tabl
%o -- _Reinhard Zumkeller_, Nov 18 2012
%Y Cf. A002627 (row sums).
%K nonn,tabl,easy
%O 1,3
%A _Alford Arnold_, Oct 26 2010
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