A084759 Composite numbers in ascending order such that the difference of successive terms is unique. a(m) - a(m-1) = a(k) - a(k-1) iff m = k.

4, 6, 9, 10, 14, 20, 25, 32, 40, 49, 60, 70, 82, 95, 110, 124, 140, 158, 175, 194, 214, 235, 258, 280, 304, 329, 355, 382, 410, 440, 469, 500, 532, 565, 600, 634, 670, 707, 745, 784, 824, 865, 908, 950, 994, 1040, 1085, 1132, 1180, 1230, 1281, 1330, 1382, 1435

Offset: 1

Author

Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Jun 17 2003

Keywords

• nonn

Comments

The sequence of first differences is 2, 3, 1, 4, 6, 5, 7, 8, 9, 11, 10, 12, 13, 15, 14, 16, 18, 17, 19, 20, 21, 23, 22, 24, 25, 26, 27, 28, ... Conjecture: every number is a term of this sequence. For every number r there exists some k such that a(k) - a(k-1) = r.

Examples

			The term after 14 is 20 and not 18 or 16 as 6-4 = 16-14 = 2, 18-14 = 14-10 = 4.
		

Crossrefs

Cf. A002808, A084758.

Extensions

More terms from David Wasserman, Jan 05 2005