A169755 A variation on Recamán's sequence A005132: see Comments for definition.

1, 3, 2, 5, 9, 4, 10, 8, 15, 7, 16, 6, 17, 14, 26, 13, 27, 12, 28, 11, 29, 25, 20, 39, 19, 40, 18, 41, 35, 59, 34, 60, 33, 61, 32, 62, 31, 24, 56, 23, 57, 22, 58, 21, 29, 67, 106, 66, 107, 65, 108, 64, 55, 45, 90, 44, 91, 43, 92, 42, 93, 82, 30, 83, 71, 125, 70, 126, 69, 127, 68

Offset: 1

Author

Rodolfo Kurchan, Apr 08 2010

Keywords

• nonn

Comments

We start with two sequences A and B. Here sequences A and B are both taken to be 1,2,3,4,5,6,7,....

We start with the first term of sequence A (which is 1).

To extend the sequence, we first try to subtract the next term of A from the current term, but that is allowed only if the result is a positive number not already in the sequence.

If that fails, we next try to subtract the next term of B from the current term, but again that is allowed only if the result is a positive number not already in the sequence.

If that fails, we next try to add the next term of A to the current term, but again that is allowed only if the result is a positive number not already in the sequence.

Finally, if that fails, we add the next term of B to the current term (this may produce repeated terms, but that is allowed at this step).

Crossrefs

Cf. A005132, A169748-A169752.

Extensions

Corrected and extended by D. S. McNeil, May 09 2010