I’ve always liked troff/eqn, which had a focus on human readable equation input. Here’s that example in eqn: verbose but very natural, almost how you would say

I’ve always liked troff/eqn, which had a focus on human readable equation input. Here’s that example in eqn: verbose but very natural, almost how you would say it out loud. .EQ W sub {delta sub 1 rho sub 1 sigma sub 2} sup {3 beta} = U sub {delta sub 1 rho sub 1} sup {3 beta} + 1 over {8 pi sup 2} int from alpha sub 1 to alpha sub 2 d alpha prime sub 2 left [ { U sub {delta sub 1 rho sub 1} sup {2 beta} - alpha prime sub 2 U sub {rho sub 1 sigma sub 2} sup {1 beta} } over U sub {rho sub 1 sigma sub 2} sup {0 beta} right ] .EN Even better if you use a little bit of Unicode (which any modern troff supports): .EQ W sub {δ sub 1 ρ sub 1 σ sub 2} sup {3 β} = U sub {δ sub 1 ρ sub 1} sup {3 β} + 1 over {8 pi sup 2} int from α sub 1 to α sub 2 d α prime sub 2 left [ { U sub {δ sub 1 ρ sub 1} sup {2 β} - α prime sub 2 U sub {ρ sub 1 σ sub 2} sup {1 β} } over U sub {ρ sub 1 σ sub 2} sup {0 β} right ] .EN