Mathematical Constants:
golden mean-1.618033989
ramanujan-soldner constant-1.4513692349
omega-0.567143290409783872999968662210
iomega-1.763222834351896710225201776
levy-3.27582291872181115978768
varga-9.2890254919208189187554494359517450610317
weier-0.4749493799879206503325046363
thuemors-0.412454033640107597783361
salem-1.1762808182599175065440703384740350506934158
robbin-0.661707182267176235155831133248413581746400
parking-0.74759792025341143517873094363652421026172
paris-1.098641964394156485734668917343596210873348396
lehmer-0.59263271820163619710407860499570146908427540719
hafner-0.3532363718549959845435165504326820112801647785
golomb-0.6243299885435508709929363831008372441796426201805
gkw-0.30366300289873265859744812190
froda-6.58088599101792097085154240388648649157307743
pi-3.1415926535
e-2.71828182845
gamma-0.5772156649
zeta-1.20205690315
catalan's constant-0.915965594
khintchines constant-2.685452001

Note: These are not all the constants that are used in math, just some of the ones that may be more important than others.
Note: These are not all the symbols used in math, just some of the more common ones used. Different levels of math used different symbols.