A143956 Triangle read by rows, A000012 * A136521 * A000012; 1<=k<=n.
1, 3, 2, 5, 4, 2, 7, 6, 4, 2, 9, 8, 6, 4, 2, 11, 10, 8, 6, 4, 2, 13, 12, 10, 8, 6, 4, 2, 15, 14, 12, 10, 8, 6, 4, 2, 17, 16, 14, 12, 10, 8, 6, 4, 2, 19, 18, 16, 14, 12, 10, 8, 6, 4, 2, 21, 20, 18, 16, 14, 12, 10, 8, 6, 4, 2
Offset: 1
Examples
First few rows of the triangle = 1; 3, 2; 5, 4, 2; 7, 6, 4, 2; 9, 8, 6, 4, 2; 11, 10, 8, 6, 4, 2; 13, 12, 10, 8, 6, 4, 2; 15, 14, 12, 10, 8, 6, 4, 2; ...
Comments