Library /sys$common/syshlp/ncphelp.hlb SET, EXECUTOR, MAXIMUM BROADCAST NONROUTERS number  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 Specifies the maximum total number of nonrouting nodes (end nodes)
 the executor node can have on its broadcast circuits.  Use a number
 in the range of 1 to 1023.  The default is 64.