A359652 Lexicographically earliest sequence of positive integers such that no three terms a(j), a(j+k), a(j+2k) (for any j and k) form an arithmetic or geometric progression.

1, 1, 2, 1, 1, 2, 2, 5, 5, 1, 1, 2, 1, 1, 2, 2, 5, 5, 2, 5, 5, 6, 6, 10, 6, 6, 11, 1, 1, 2, 1, 1, 2, 2, 5, 5, 1, 1, 2, 1, 1, 2, 2, 5, 5, 2, 5, 5, 6, 6, 10, 6, 6, 11, 11, 5, 5, 6, 6, 12, 6, 6, 12, 2, 12, 14, 13, 13, 3, 13, 12, 12, 15, 13, 12, 12, 13, 15, 13, 17

Offset

1,3

Links

Alois P. Heinz, Table of n, a(n) for n = 1..10000

Formula

a(n) <= (n^2+1)/2.

Crossrefs

Cf. A229037, A268811.

Sequence in context: A318205 A046772 A348291 * A179974 A387203 A246402

Adjacent sequences: A359649 A359650 A359651 * A359653 A359654 A359655

Keyword

nonn,look

Author

Neal Gersh Tolunsky, Jan 09 2023

Extensions

More terms from Alois P. Heinz, Jan 09 2023

Status

approved