The BOOST_PP_LIMIT_SEQ macro
defines the maximum seq size supported by the library.
Usage
BOOST_PP_LIMIT_SEQ
Remarks
This macro expands by default to 256. For a C++ standard
conforming preprocessor, the macro actually expands to the value
of the BOOST_PP_LIMIT_MAG
macro, but can be set to a lower value than BOOST_PP_LIMIT_MAG if
desired, but never to a higher value.