A090324 Second in a series of triangular arrays generating the natural numbers (cf. A079946).

6, 13, 10, 27, 21, 18, 55, 43, 37, 34, 111, 87, 75, 69, 66, 223, 175, 151, 139, 133, 130, 447, 351, 303, 279, 267, 261, 258, 895, 703, 607, 559, 535, 523, 517, 514

Offset: 1

Author

Alford Arnold, Jan 26 2004

Keywords

• easy
• nonn
• tabl

Comments

Note that for each triangular array T(row+1,col) = 2 * T(row,col) +1 and that the change from T(row,col+1) to T(row,col) can be readily discerned. In the first array that pattern is 1 2 4 8 ...while in the second, it becomes 3 6 12 24 48 ... and in general, the pattern for the k-th array will begin with 2k-1.

Examples

			The first array begins
1
3 2
7 5 4
15 11 9 8
31 23 19 17 16
so a(1) begins with six. In general each triangular array will begin with
the next term from A079946.