1,2

Each ordered pair (a(k),a(k-1)) occurs at most once in the sequence.

Paul Tek, Table of n, a(n) for n = 1..2473

Cf. A175500.

Sequence in context: A305800 A293442 A318470 * A144370 A239514 A304464

Adjacent sequences: A175498 A175499 A175500 * A175502 A175503 A175504

nonn

Leroy Quet, May 31 2010

Terms a(26) and beyond from b-file by Andrew Howroyd, Feb 05 2018

approved