A265691 Irregular triangle read by rows: row n gives lexicographically first addition chain of minimal length for n.

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

Offset

1,3

Comments

The addition chains in this sequence for 1, 2, 3, 7 start respectively with 1, 1,2, 1,2,3, and 1,2,3,4. Are there minimal addition chains starting 1,2,3,4,5? 1,2,...,n for larger n?

Needs a b-file.

Links

Table of n, a(n) for n=1..95.

Example

The table starts:
1
1 2
1 2 3
1 2 4
1 2 3 5
1 2 3 6
1 2 3 4 7
1 2 4 8
...

Crossrefs

Cf. A265690 (row lengths), A265692 (largest).

Sequence in context: A334428 A126260 A264846 * A334430 A214614 A265692

Adjacent sequences: A265688 A265689 A265690 * A265692 A265693 A265694

Keyword

nonn,tabf,nice

Author

Franklin T. Adams-Watters, Dec 13 2015

Status

approved