A127447 Triangle defined by the matrix product A127446 * A054521, read by rows 1<=k<=n.

1, 4, 0, 6, 3, 0, 12, 0, 4, 0, 10, 5, 5, 5, 0, 24, 6, 0, 0, 6, 0, 14, 7, 7, 7, 7, 7, 0, 32, 0, 16, 0, 8, 0, 8, 0, 27, 18, 0, 9, 9, 0, 9, 9, 0, 40, 10, 20, 10, 0, 0, 10, 0, 10, 0, 22, 11, 11, 11, 11, 11, 11, 11, 11, 11, 0, 72, 12, 12, 0, 24, 0

Offset: 1

Author

Gary W. Adamson, Jan 14 2007

Keywords

• nonn
• tabl

Examples

			First few rows of the triangle are:
1;
4, 0;
6, 3, 0;
12, 0, 4, 0;
10, 5, 5, 5, 0;
24, 6, 0, 0, 6, 0;
14, 7, 7, 7, 7, 7, 0;
32, 0, 16, 0, 8 0, 8, 0;
...
		

Crossrefs

Cf. A038040 (column k=1), A000290 (row sums), A127446, A054521.

Programs

Maple

A054521 := proc(n, k) if igcd(n,k) = 1 then 1; else 0; fi; end:
A127447 := proc(n,k)
        add( A127446(n,j)*A054521(j,k),j=k..n) ;
end proc:
seq(seq(A127447(n,m),m=1..n),n=1..12) ; # R. J. Mathar, Nov 08 2011

Formula

T(n,k) = Sum_{j=k..n} A127446(n,j) * A054521(j,k).