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%I #4 Mar 31 2012 08:58:36
%S 1,1,1,1,4,1,1,1,1,1,1,16,27,4,1,1,1,1,1,1,1,1,4,1,16,1,4,1,1,1,9,1,1,
%T 9,1,1,1,16,1,4,25,16,1,4,1,1,1,1,1,1,1,1,1,1,1,1,4,27,128,1,108,1,16,
%U 9,4,1,1,1,1,1,1,1,1,1,1,1,1,1,1,16,1,4,1,16,49,4,1,16,1,4,1,1,1,27,1
%N Triangle with elements A120070(m,n)/A120072(m,n) read by rows, m>=2, 1<=n<m.
%e The triangle starts in row m=2 as
%e 1;
%e 1, 1;
%e 1, 4, 1;
%e 1, 1, 1, 1;
%e 1, 16, 27, 4, 1;
%e 1, 1, 1, 1, 1, 1;
%e 1, 4, 1, 16, 1, 4, 1;
%p A120070 := proc(m,n) m^2-n^2 ; end: A120072 := proc(m,n) numer(1/n^2-1/m^2) ; end:
%p A164561 := proc(m,n) A120070(m,n)/A120072(m,n) ; end: seq( seq(A164561(m,n),n=1..m-1), m=2..30) ; # _R. J. Mathar_, Aug 19 2009
%K nonn,tabl,easy
%O 2,5
%A _Paul Curtz_, Aug 16 2009
%E Edited and extended by _R. J. Mathar_, Aug 19 2009