OFFSET
1,1
COMMENTS
This was originally based on the data in Jinyuan Wang's A324042, and then extended by Lars Blomberg.
It would be nice to have a formula for these entries. It is easy to see that the first column is 2n+3 for n>1.
LINKS
Lars Blomberg, Table of n, a(n) for n = 1..3240 (the first 80 rows)
Lars Blomberg, Scott R. Shannon and N. J. A. Sloane, Graphical Enumeration and Stained Glass Windows, 1: Rectangular Grids, (2021). Also arXiv:2009.07918.
EXAMPLE
Triangle begins:
4,
7, 7,
9, 14, 9,
11, 24, 24, 11,
13, 30, 38, 30, 13,
15, 38, 60, 60, 38, 15,
17, 44, 76, 86, 76, 44, 17,
...
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
N. J. A. Sloane, Mar 20 2020
EXTENSIONS
a(29) and beyond from Lars Blomberg, Apr 23 2020
STATUS
approved