0

Output the flattened version of the sequence A297359, which starts like the following:

1, 1, 1, 1, 2, 1, 1, 3, 3, 1, 2, 4, 6, 4, 2, 1, 6, 10, 10, 6, 1,
1, 7, 16, 20, 16, 7, 1, 3, 8, 23, 36, 36, 23, 8, 3, 3, 11, 31, 59,
72, 59, 31, 11, 3, 1, 14, 42, 90, 131, 131, 90, 42, 14, 1,...
----------------
                  1,
                1,   1,
              1,  2,   1,
            1,  3,   3,  1,
          2,  4,  6,   4,  2,
        1,  6,  10, 10,  6,  1,
      1, 7,  16,  20,  16,  7, 1,
    3, 8,  23,  36, 36,  23,  8, 3,
  3, 11, 31, 59,  72,  59, 31, 11, 3,
1, 14, 42, 90, 131, 131, 90, 42, 14, 1,
...

The defining property of the sequence is that

  • the entire triangle is generated like the Pascal’s triangle, and
  • the left and right boundaries are identical to the entire triangle read by rows.

Standard rules and I/O methods apply. The shortest code in bytes wins.