4.3BSD-Tahoe/usr/lib/learn/eqn/L1.1a

#print
To properly print a file containing an equation,
you have to type a longer-than-usual command line.
If you are using a DASI or GSI, to print a file
"math" that contains mathematics, you must say

  neqn math | nroff -Txxx

where "-Txxx" describes the terminal you are using.
This is usually one of
  -T300
  -T300S
  -T450
It is very important that you get this line right.
If you don't, you'll not be happy with your output.

In this directory is a file called "Example"; print
it properly, using whichever command line is 
appropriate to your terminal.
Then type "ready".
#once #create Example
This is a little file that contains an
example of a subscript and superscript:
.ce
.EQ
a sub i + b sub i ~=~ c sub i sup 2
.EN
.pl 1
#copyin
#user
#uncopyin
grep 'neqn Example *| *nroff -T' <.copy >/dev/null
#log
#next
1.1b 10