'''	\"  eqn file | troff -mm [-Tdevname] | ...
.PH "'EQN:  File(\n(.F)''Device(\*(.T)'"
.P
.DS I
.EQ
(N sub roman Sh ) sub a sup * mark = 1 over 2 left ( d sub t over L right )
  N sub roman Re N sub roman Sc
.EN
.sp
.EQ (3a)
lineup times
left [
{ 1 - sum from j=1 to {j= inf} {-4 beta sub j} over {beta sub j sup 2}
  left ( {d phi sub j} over dr sub + right ) sub {r sub + =1}
  exp left ( {- beta sub j sup 2 (x/r sub t ) } over { N sub Re N sub roman Sc} right ) 
}
over
{ 1 + sum from j=1 to {j= inf} {-4 beta sub j} over {beta sub j sup 2}
  left ( {d phi sub j} over dr sub + right ) sub {r sub + =1}
  exp left ( {- beta sub j sup 2 (x/r sub t ) } over { N sub Re N sub roman Sc} right ) 
}
right ]
.EN
.DE
.sp 1i
.P
.B Knuth
(Vol. 1, p. 92):
.DS CB
.EQ
G(z)~mark =~ e sup { ln ~ G(z) }
~=~ exp left ( 
sum from k>=1 {S sub k z sup k} over k right )
~=~  prod from k>=1 e sup {S sub k z sup k /k}
.EN
.sp .5
.EQ
lineup =~ left ( 1 + S sub 1 z + 
{ S sub 2 sup 1 z sup 2 } over 2! + ... right )
left ( 1+ { S sub 2 z sup 2 } over 2
+ { S sub 2 sup 2 z sup 4 } over { 2 sup 2 . 2! }
+ ... right ) ...
.EN
.sp .5
.EQ
lineup =~  sum from m>=0 left ( I
sum from
pile { k sub 1 ,k sub 2 , ... ,k sub m  >=0
  above
k sub 1 +2k sub 2 + ... +mk sub m =m}
{ S sub 1 sup {k sub 1} } over {1 sup k sub 1 k sub 1 ! } ~
{ S sub 2 sup {k sub 2} } over {2 sup k sub 2 k sub 2 ! } ~
...
{ S sub m sup {k sub m} } over {m sup k sub m k sub m ! } 
right ) z sup m
.EN
.DE
