/usr/include/NTL/gmp_aux.h is in libntl-dev 5.5.2-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2
#define NTL_ZZ_NBITS (64) #define NTL_ZZ_FRADIX (((double)(1L<<62))*((double)(1L<<2)))