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Triangle T(n,m) = (3*n+3*m-2)*(n+1-m)/2 read by rows.
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%I #13 May 16 2021 12:16:57

%S 2,7,5,15,13,8,26,24,19,11,40,38,33,25,14,57,55,50,42,31,17,77,75,70,

%T 62,51,37,20,100,98,93,85,74,60,43,23,126,124,119,111,100,86,69,49,26,

%U 155,153,148,140,129,115,98,78,55,29,187,185,180,172,161,147,130,110,87,61,32

%N Triangle T(n,m) = (3*n+3*m-2)*(n+1-m)/2 read by rows.

%F T(n,m) = (3*n+3*m-2)*(n+1-m)/2 .

%F T(n,m) = A094930(n,m)/(3*m-1).

%F T(n,1) = A005449(n).

%F T(n,n) = A016768(n-1).

%F Row sums: sum_{m=1..n} T(n,m) = n^2*(n+1) = A011379(n).

%e The triangle starts in row n=1 as

%e 2;

%e 7,5;

%e 15,13,8;

%e 26,24,19,11;

%o (Python)

%o def A096037(n,m):

%o return (3*n+3*m-2)*(n+1-m)//2

%o print( [A096037(n,m) for n in range(20) for m in range(1,n+1)] )

%o # _R. J. Mathar_, Oct 11 2009

%Y Cf. A094930, A024212, A011379, A002411, A096038, A095794.

%K nonn,easy,tabl

%O 1,1

%A _Gary W. Adamson_, Jun 17 2004

%E Edited and extended, A-numbers corrected by _R. J. Mathar_, Oct 11 2009