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A127701 Infinite lower triangular matrix with (1, 2, 3, ...) in the main diagonal, (1, 1, 1, ...) in the subdiagonal and the rest zeros.

%I A127701 #12 Jun 05 2021 01:37:58
%S A127701 1,1,2,0,1,3,0,0,1,4,0,0,0,1,5,0,0,0,0,1,6,0,0,0,0,0,1,7,0,0,0,0,0,0,
%T A127701 1,8,0,0,0,0,0,0,0,1,9,0,0,0,0,0,0,0,0,1,10,0,0,0,0,0,0,0,0,0,1,11,0,
%U A127701 0,0,0,0,0,0,0,0,0,1,12,0,0,0,0,0,0,0,0,0,0,0,1,13,0,0,0,0,0,0,0,0,0,0,0,0
%N A127701 Infinite lower triangular matrix with (1, 2, 3, ...) in the main diagonal, (1, 1, 1, ...) in the subdiagonal and the rest zeros.
%C A127701 Eigensequence of the triangle = A001040 starting (1, 3, 10, 43, 225, ...). - _Gary W. Adamson_, Dec 29 2008
%e A127701 First few rows of the triangle are:
%e A127701   1;
%e A127701   1, 2;
%e A127701   0, 1, 3;
%e A127701   0, 0, 1, 4;
%e A127701   0, 0, 0, 1, 5;
%e A127701   0, 0, 0, 0, 1, 6;
%e A127701   0, 0, 0, 0, 0, 1, 7;
%e A127701   ...
%t A127701 Join[{1},Flatten[Table[Join[{PadRight[{},n-2,0],1,n}],{n,2,15}]]] (* _Harvey P. Dale_, Jan 06 2014 *)
%Y A127701 Cf. A001040. - _Gary W. Adamson_, Dec 29 2008
%K A127701 nonn,easy,tabl
%O A127701 1,3
%A A127701 _Gary W. Adamson_, Jan 23 2007
%E A127701 More terms from _Jon E. Schoenfield_, May 26 2007