A171084 A "run" means a maximal string of decreasing numbers; this sequence has the property that the sequence of run lengths is the sequence itself and all natural numbers appear exactly once.

2, 1, 3, 6, 5, 4, 12, 11, 10, 9, 8, 7, 17, 16, 15, 14, 13, 21, 20, 19, 18, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 54, 53, 52, 51, 50, 49, 48, 47, 46, 45, 63, 62, 61, 60, 59, 58, 57, 56, 55, 71, 70, 69, 68

Offset

1,1

Links

Lars Blomberg, Table of n, a(n) for n = 1..10000

Eric Angelini, Runs

E. Angelini, Runs [Cached copy, with permission]

Example

Here is the same sequence with stars demarking the runs: 2, 1, * 3, * 6, 5, 4, * 12, 11, 10, 9, 8, 7, * 17, 16, 15, 14, 13, * 21, 20, 19, 18, * 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, * 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, * 54, 53, 52, 51, 50, 49, 48, 47, 46, 45, * 63, ...

Crossrefs

Sequence in context: A120576 A063707 A205840 * A332318 A118287 A024930

Adjacent sequences: A171081 A171082 A171083 * A171085 A171086 A171087

Keyword

nonn

Author

N. J. A. Sloane, Sep 07 2010, based on a posting to the Sequence Fans Mailing List by Eric Angelini, Aug 23 2010.

Extensions

a(55)-a(67) from Lars Blomberg, Nov 23 2013

Status

approved