regular expression problem

hi everyone
there is a way, using re, to test (for es) in
a=[a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14] if a list b is
composed by three "sublists" of a separated or not by elements.

if b=[a2,a3,a4,a7,a8,a12,a13] gives true because in a
we have [....,a2,a3,a3,...,a7,a8,...,a12,a13,...]
or b=[a1,a2,a5,a14] gives true because in a we have
[a1,a2,....,a5,...,a14] and so on...

thank in advance.
giorgio borghi

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