This is The Pi Song (100 Digits of π) by AsapScience. Click the green flag so it doesn't lag . If the audio goes with the video, then your good. If it doesn't watch it in default mode, not fullscreen and click the green flag a couple of times. Sorry if it lags out at the end.
Microsoft Clipchamp for converting everything to GIF's Music Downloader for MP4 (Video) and MP3 (Music) of video
