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A162995 A scaled version of triangle A162990. 5

%I

%S 1,3,1,12,4,1,60,20,5,1,360,120,30,6,1,2520,840,210,42,7,1,20160,6720,

%T 1680,336,56,8,1,181440,60480,15120,3024,504,72,9,1,1814400,604800,

%U 151200,30240,5040,720,90,10,1

%N A scaled version of triangle A162990.

%C We get this scaled version of triangle A162990 by dividing the coefficients in the left hand columns by their 'top-values' and then taking the square root.

%C T(n,k) = A173333(n+1,k+1), 1 <= k <= n. - _Reinhard Zumkeller_, Feb 19 2010

%C T(n,k) = A094587(n+1,k+1), 1 <= k <= n. - _Reinhard Zumkeller_, Jul 05 2012

%H Reinhard Zumkeller, <a href="/A162995/b162995.txt">Rows n = 1..150 of triangle, flattened</a>

%F a(n,m) = (n+1)!/(m+1)! for n = 1, 2, 3, ..., and m = 1, 2, ..., n.

%e The first few rows of the triangle are:

%e [1]

%e [3, 1]

%e [12, 4, 1]

%e [60, 20, 5, 1]

%p a := proc(n, m): (n+1)!/(m+1)! end: seq(seq(a(n, m), m=1..n), n=1..9); # _Johannes W. Meijer_, revised Nov 23 2012

%o (Haskell)

%o a162995 n k = a162995_tabl !! (n-1) !! (k-1)

%o a162995_row n = a162995_tabl !! (n-1)

%o a162995_tabl = map fst $ iterate f ([1], 3)

%o where f (row, i) = (map (* i) row ++ [1], i + 1)

%o -- _Reinhard Zumkeller_, Jul 04 2012

%Y Cf. A094587.

%Y A056542(n) equals the row sums for n>=1.

%Y A001710, A001715, A001720, A001725, A001730, A049388, A049389, A049398, A051431 are related to the left hand columns.

%Y A000012, A009056, A002378, A007531, A052762, A052787, A053625 and A159083 are related to the right hand columns.

%K easy,nonn,tabl

%O 1,2

%A _Johannes W. Meijer_, Jul 27 2009

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Last modified November 14 20:15 EST 2019. Contains 329130 sequences. (Running on oeis4.)