
EXAMPLE

n, a(n), example of optimal S:
1, 1, [1]
2, 2, [1, 2]
3, 4, [1, 3, 4]
4, 6, [1, 2, 4, 5]
5, 8, [2, 3, 5, 6]
6, 10, [3, 4, 6, 7]
7, 13, [1, 5, 7, 8, 10]
8, 16, [1, 2, 7, 8, 10, 11]
9, 20, [1, 3, 4, 9, 10, 12, 13]
10, 24, [1, 2, 4, 5, 10, 11, 13, 14]
11, 28, [2, 3, 5, 6, 11, 12, 14, 15]
12, 32, [3, 4, 6, 7, 12, 13, 15, 16]
13, 36, [4, 5, 7, 8, 13, 14, 16, 17]
14, 40, [5, 6, 8, 9, 14, 15, 17, 18]
...
For example, the line 5, 8, [2, 3, 5, 6] corresponds to the triangle
....1....
...0.1...
..1.1.0..
.1.0.1.0.
0.1.1.0.0
and the value a(5) = 8.
It is a plausible conjecture that any optimal solution S here is also an optimal solution to the square grid version in A269745, and vice versa. (The square grid being obtained by reflecting the triangle in its base.)
