How many ways can hexagonal tiles of side a be arranged in a b*a sided triangle?

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How many ways can hexagonal tiles can be arranged in a triangle?

Let us assume that there is an equilateral triangle of side $s$. The triangle is subdivided by edges on $b$ segments, so that there are $b^2$ smaller equilateral triangles inside, in a triangular fragment of hexagonal lattice.

There are hexagonal tiles of side $a=s/b$.

How can we count the number ($L$) of different arrangement of the hexagonal tiles inside the triangle, if there is a condition that the tiles must touch by vertices or by sides and fit into triangle?

One of the solutions is as in uniform tiling hexadeltile $3.6^2$. The other one is a fragment of regular tiling - homeycomb ($6^3$). But how many total ways ($L$) there are?

The problem is also in finding the number of cases with the same number ($C$) of the hexagonal tiles within the given subdivision.

For example:
if we divide the triangle on $b=5$
the total number of different arrangements $L= 4$.
There are: $1$ case ($L_1$) with $3$ tiles ($C_1=3$) and 3 cases ($L_3$) with $2$ tiles ($C_2=3$).

I have tried to solve this with some combinatorics, but the best results I could achieve is to draw all the cases (from $b = 3$ to $b=8$) and count them... Help.

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