Is the third day timeframe of Jesus burial/resurrection required for salvation?

In 1 Corinthians 15:1-4, Paul states the Gospel that saves: that Jesus died for our sins, was buried, and rose again on the third day. I have heard multiple versions of this when people teach people how to be saved, often in these two ways: 1. believe Jesus died for your sins, was buried, and rose again so you could be saved (no mention of the third day, just that he rose again) 2. believe Jesus died for your sins and rose again so you could be saved. Notice how the third day was not mentioned, nor the burial in the second one. Why are they omitted? If one believes in either of those two for salvation, are they still unsaved? Romans 6 seems to claim that Jesus was buried so we could be saved, too. Why would Jesus wanna make us believe in a timeframe to be saved? Yes, we should believe it, but do we have to believe the 3rd day part to BE saved?