Plan 9 from Bell Labs’s /usr/web/sources/contrib/steve/root/sys/lib/texmf/metapost/base/troffnum.mp
% Default init_numbers for use with troff % Don't input this directly--format.mp uses this file init_numbers(btex$-$etex, btex$1$etex, btex$ times 10$etex, btex$"" sup -$etex, btex$"" sup 2$etex); Fe_base := btex $10$ etex;