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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.
1
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, 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, 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
OFFSET
1,1
COMMENTS
(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.
FORMULA
T(n,k) = [y+1]^2-y^2
EXAMPLE
Northwest corner:
3 2 1 5 4
5 1 4 9 5
7 7 9 13 4
9 4 1 17 1
CROSSREFS
Sequence in context: A291455 A248849 A172216 * A197293 A099643 A224344
KEYWORD
nonn,tabl
AUTHOR
Clark Kimberling, Aug 02 2006
STATUS
approved