That's a very carefully constructed sentence, as a candidate and PEOTUS the lies were tiresome, but he's only been POTUS for 4 days. Are you counting the lies from his representatives and websites, in which case we can already include Spicer's comments about it being the 'biggest inauguration ever. Period' and misleading Washington DC crime statistics, but if you're limiting it to just his live broadcast words and tweets, then we're left with the lie about it not raining during his speech.
I suppose 1 outright lie in 4 days isn't too bad.