%I #24 Nov 19 2023 01:58:31

%S 1,1,1,1,1,1,1,2,2,1,1,1,1,1,2,3,4,5,4,2,2,1,1,1,2,3,5,9,12,15,17,15,

%T 7,4

%N Irregular triangle read by rows: T(n,k) = number of cells of dimension k in the tropical Schottky locus of genus n.

%C Row n has 3n + 1 entries, for 0 <= k <= 3n.

%H Melody Chan, <a href="http://dx.doi.org/10.2140/ant.2012.6.1133">Combinatorics of the tropical Torelli map</a>, Algebra Number Theory, 6 (2012), 1133-1169.

%e The irregular triangle T(n,k) begins:

%e n\k 0 1 2 3 4 5 6 7 8 9 10 11 12...

%e 2: 1, 1, 1, 1;

%e 3: 1, 1, 1, 2, 2, 1, 1;

%e 4: 1, 1, 1, 2, 3, 4, 5, 4, 2, 2;

%e 5: 1, 1, 1, 2, 3, 5, 9, 12, 15, 17, 15, 7, 4;

%e ...

%Y Row sums are A220444.

%K nonn,tabf,more

%O 2,8

%A _Harry Richman_, Oct 23 2023