A097288 Rectangular array read by antidiagonals obtained from A097287 by deleting the zeros.

2, 1, 6, 3, 4, 12, 7, 5, 8, 20, 13, 9, 10, 14, 30, 21, 15, 11, 16, 22, 42, 31, 23, 17, 18, 24, 32, 56, 43, 33, 25, 19, 26, 34, 44, 72, 57, 45, 35, 27, 28, 36, 46, 58, 90, 73, 59, 47, 37, 29, 38, 48, 60, 74, 110, 91, 75, 61, 49, 39, 40, 50, 62, 76, 92, 132, 111, 93, 77, 63, 51

Offset: 1

Author

Clark Kimberling, Aug 05 2004

Keywords

• nonn
• tabl

Comments

As a sequence, this is a permutation of the natural numbers. Evens lie on or below the main diagonal; odds, above. The triangle formed by the evens is twice that of A066182.

Examples

			Northwest corner:
2 1 3 7 13
6 4 5 9 15
12 8 10 11 17
20 14 16 18 19
		

Crossrefs

Cf. A097287.