A067802 Triangle with T(n,k)=C(2n+1,n-k)^2*(2k+1)/(2n+1).

1, 3, 1, 20, 15, 1, 175, 189, 35, 1, 1764, 2352, 720, 63, 1, 19404, 29700, 12375, 1925, 99, 1, 226512, 382239, 196625, 44044, 4212, 143, 1, 2760615, 5010005, 3006003, 869505, 124215, 8085, 195, 1, 34763300, 66745536, 45048640, 15767024, 2998800

Offset

0,2

Links

Table of n, a(n) for n=0..40.

Formula

a(n) =A034869(2n+1, k)*A039599(n, k). Row sums are C(2n, n)^2=A002894(n).

Example

Rows are: 1; 3,1; 20,15,1; 175,189,35,1; etc. T(3,1)=C(7,2)^2*3/7=21^2*3/7=189.

Crossrefs

First column is A000891.

Sequence in context: A374651 A038455 A343890 * A181832 A139723 A030042

Adjacent sequences: A067799 A067800 A067801 * A067803 A067804 A067805

Keyword

nonn,tabl

Author

Henry Bottomley, Feb 07 2002

Status

approved