A306717 Square array T(n, k) of positive integers, n > 0, k > 0, read by antidiagonals, filled the greedy way, such that for any i >= 0 and j >= 0 with i + j > 0, no three terms T(n, k), T(n+i, k+j), T(n+2*i, k+2*j) form an arithmetic progression.

1, 1, 1, 2, 1, 2, 1, 2, 2, 1, 1, 1, 3, 1, 1, 2, 1, 2, 2, 1, 2, 2, 2, 2, 1, 2, 2, 2, 4, 2, 3, 1, 1, 3, 2, 4, 4, 4, 5, 2, 1, 2, 5, 4, 4, 1, 4, 5, 4, 2, 2, 4, 5, 4, 1, 1, 1, 7, 2, 4, 3, 4, 2, 7, 1, 1, 2, 1, 2, 5, 4, 5, 5, 4, 5, 2, 1, 2, 1, 2, 5, 1, 5, 5, 4, 5, 5

Offset

1,4

Comments

This sequence is a 2-dimensional variant of A229037.

Links

Table of n, a(n) for n=1..87.

Rémy Sigrist, Colored representation of T(n, k) for n = 1..1000 and k = 1..1000 (where the hue is function of T(n, k))

Rémy Sigrist, C++ program for A306717

Formula

T(n, k) = T(k, n).

T(n, 1) = T(n, 2) = A229037(n).

Prog

(C++) See Links section.

Crossrefs

Cf. A229037.

Sequence in context: A327164 A094781 A023582 * A195969 A023518 A326194

Adjacent sequences: A306714 A306715 A306716 * A306718 A306719 A306720

Keyword

nonn,tabl

Author

Rémy Sigrist, Mar 06 2019

Status

approved