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Triangle T(n,m) read by rows: product A127093 * A127094.
6

%I #7 Aug 12 2015 21:19:32

%S 1,5,2,10,0,3,21,2,8,4,26,0,0,0,5,50,2,3,18,12,6,50,0,0,0,0,0,7,85,2,

%T 8,4,32,0,16,8,91,0,3,0,0,0,27,0,9,130,2,0,0,5,50,0,0,20,10,122,0,0,0,

%U 0,0,0,0,0,0,11,210,2,11,22,12,6,72,0,48,36,24,12,170,0,0,0,0,0,0,0,0,0,0,0,13,250,2,0,0,0,0,7,98,0

%N Triangle T(n,m) read by rows: product A127093 * A127094.

%C A127097 is a close companion.

%F T(n,m) = Sum_{k=m..n} A127093(n,k)*A127094(k,m).

%F Row sums: Sum_{m=1..n} T(n,m) = A001001(n).

%F Left column: T(1,m) = A001157(m).

%e First few rows of the triangle are:

%e 1;

%e 5, 2;

%e 10, 0, 3;

%e 21, 2, 8, 4;

%e 26, 0, 0, 0, 5;

%e 50, 2, 3, 18, 12, 6;

%e 50, 0, 0, 0, 0, 0, 7;

%e 85, 2, 8, 4, 32, 0, 16, 8;

%p A127093 := proc(n,m) if m> n or m<1 or n < 1 then 0 ; elif (n mod m) = 0 then m; else 0 ; fi; end:

%p A127094 := proc(n,m) A127093(n,n-m+1) ; end: A127098 := proc(n,m) add( A127093(n,k)*A127094(k,m),k=1..n) ; end:

%p for n from 1 to 30 do for m from 1 to n do printf("%d,",A127098(n,m)) ; od: od: # _R. J. Mathar_, Mar 02 2009

%Y Cf. A127097, A127093, A127094, A001001, A001157.

%K nonn,tabl,easy

%O 1,2

%A _Gary W. Adamson_, Jan 05 2007

%E Edited and extended by _R. J. Mathar_, Mar 02 2009