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A121490 Rectangular array T by antidiagonals: T(n,k) = [y+1]^2-y^2, where y=n*sqrt(k) and [ ] denotes the floor function.

%I A121490 #2 Mar 30 2012 18:57:06
%S A121490 3,2,5,1,1,7,5,4,7,9,4,9,9,4,11,3,5,13,1,14,13,2,1,4,17,6,9,15,1,8,10,
%T A121490 1,21,13,2,17,7,4,1,4,19,25,22,16,19,6,13,9,9,19,16,29,4,7,21,5,9,19,
%U A121490 16,21,9,11,33,13,25,23,4,5,10,25,25,4,30,4,37,24,14,25,3,1,1,9,31,1,18,16
%N A121490 Rectangular array T by antidiagonals: T(n,k) = [y+1]^2-y^2, where y=n*sqrt(k) and [ ] denotes the floor function.
%C A121490 (Row 1)=A080883; (Column 1)=A005408 except for initial term; (Column 2)=A087059; (Column 3)=A120865; (Column 4)=A016813 except for initial term; (Column 5)=A120867; Columns 1,4,9,16,25,... are arithmetic sequences; (Main diagonal)=A121489.
%F A121490 T(n,k) = [y+1]^2-y^2
%e A121490 Northwest corner:
%e A121490 3 2 1 5 4
%e A121490 5 1 4 9 5
%e A121490 7 7 9 13 4
%e A121490 9 4 1 17 1
%K A121490 nonn,tabl
%O A121490 1,1
%A A121490 _Clark Kimberling_, Aug 02 2006