Il seguente codice dovrebbe risolvere i tuoi problemi:
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0 \ar[d] & L – l \ar[d] & \\
X_{t_2 + L – l}(R + h) = \ar[d]_{d_{R+h}^l} & \bigg\{ X_{(L-l,l),0}^{(t_2 + 1,1,\ldots,1)}(R+t_1+l) \bigg\} \ar[d] & \\
X_{t_2 + L – l}(R + h – 1) = \ar[d] & \bigg\{\displaystyle \sum_{i + s = R + h – 1} \sum^{L-l}_{\substack{|h| = i \\ |h| \geq l}} X_{(|h|,l), L-|h|-l}^{(t_2 + h_1,h_2, \ldots, h_i)}(1) \bigg\} \ar[d] & \\
\vdots \ar[d] & \vdots \ar[d] & \\
X_{t_2 + L – l}(R + t_1 + l + 1) = \ar[d] & \bigg\{ \displaystyle \sum_{i + s = R + t_1 + l – 1} \sum^{L-l}_{\substack{|h| = i \\ |h| \geq l}} X_{(|h|,l), L-|h|-l}^{(t_2 + h_1,h_2, \ldots, h_i)}(1) \ar[d] & + & \displaystyle \sum^{L – l}_{h = l} X_{(h,l)}^{t_2 + h}(R + t_1 + l) \bigg\} \\
\vdots \ar[d] & \vdots \ar[d] & \\
X_{t_2 + L – l}(3) = \ar[d]_{d_3^l} & \bigg\{ \displaystyle \sum^{L – l}_{|h| = l} X_{(|h|, l), L – l – |h|}^{(t_2 + h_1, h_2, h_3)}(0) \ar[dr] & \oplus & \displaystyle \sum^{L – l}_{|h| = l} X_{(|h|, l), L – l – |h|}^{(t_2 + h_1, h_2)}(1) \ar[dll] \ar[d] & \oplus \displaystyle \sum_{|h| = l} X_{(|h|, l), L – l – |h|}^{(t_2 + h)}(2) \bigg\} \ar@{.>}[dlll] \\
X_{t_2 + L – l}(2) = \ar[d]_{d_2^l} & \bigg\{ \displaystyle \sum^{L – l}_{h = l} X_{(h, l), L – h – l}^{(t_2 + h)}(1) \ar[d] & \oplus & \displaystyle \sum^{L – l}_{|h| = l} X_{(|h|, l), L – l – |h|}^{(t_2 + h_1, h_2)}(0) \bigg\} \ar[dll] \\
X_{t_2 + L – l}(1) = & \bigg\{ \displaystyle \sum_{h = l}^{L – l}X_{(h,l), L – l – h}^{t_2 + h} \bigg\} & }}
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I problemi con le sommatorie a me non si presentano utilizzando il pacchetto xy e tutto il diagramma (credo si chiami cosi non ne ho mai visti) mi sta all’interno della pagina normale.
Ciao Alberto