Mascimo

20 LEDs in series will not work on 110 vac. it is actually 117 vac rms. the peak to peak is about 172 vac. the commercially made bulbs have
a .5mf cap in series with the line(limits current to 30ma max), a bridge(to rectify ac), a large electrolytic cap (to filter the dc ripple) maybe a high value resistor(for a bleeder resistor) 33 led's in series, and a current limiting resistor in series with the LEDs. typically 1200- 2k ohms or so.
if you achieve 130 vdc from your circuit a 1k limiter will work on a string of 33 leds.
for resistance -start high and go slow. be most cautious using 117vac as it can kill you. if you are young and/or inexperienced, seek help from a knowledgeable person. good luck with your project. unclecytheledguy.

Thanks for sharing your project, and welcome to Instructables!

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