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Triangle T(n,m) = A127093 * A126988 read by rows.
5

%I #7 Aug 12 2015 21:12:06

%S 1,5,2,10,0,3,21,10,0,4,26,0,0,0,5,50,20,15,0,0,6,50,0,0,0,0,0,7,85,

%T 42,0,20,0,0,0,8,91,0,30,0,0,0,0,0,9,130,52,0,0,25,0,0,0,0,10,122,0,0,

%U 0,0,0,0,0,0,0,11,210,100,63,40,0,30,0,0,0,0,0,12,170,0,0,0,0,0,0,0,0,0,0,0

%N Triangle T(n,m) = A127093 * A126988 read by rows.

%C Multiply the infinite lower triangular matrices A127093 and A126988.

%F T(n,m) = sum_{j=m..n} A127093(n,j)*A126988(j,m).

%F T(n,1) = A001157(n).

%e First few rows of the triangle are:

%e 1;

%e 5, 2;

%e 10, 0, 3;

%e 21, 10, 0, 4;

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

%e 50, 20, 15, 0, 0, 6;

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

%e ...

%p A127093 := proc(n,m) if n mod m = 0 then m; else 0 ; fi; end:

%p A126988 := proc(n,k) if n mod k = 0 then n/k; else 0; fi; end:

%p A127097 := proc(n,m) add( A127093(n,j)*A126988(j,m),j=m..n) ; end:

%p for n from 1 to 15 do for m from 1 to n do printf("%d,",A127097(n,m)) ; od: od: # _R. J. Mathar_, Aug 18 2009

%Y Cf. A126988, A000203, A127098, A001187, A001001 (row sums), A127093.

%K nonn,tabl

%O 1,2

%A _Gary W. Adamson_, Jan 05 2007

%E A-numbers corrected by _R. J. Mathar_, Aug 18 2009