>= subset sub, sup, and or not forall therexists diamondsuit
rightarrow etc.
≥ ⊆ ∪∩⊥⊦¬∀∃♦→
gr or eq: ≥
subset ⊆
diamond ♦
rightarrow →
plus or minus ±
NB and/or don't work
approx and lots of arrows still to do
also large sums and products, large brackets, 3 barred=,...