Back in 2014 I answered the question Google Spreadsheet generate random numbers with Math.random(), based on how Google Spreadsheets worked at that time: https://webapps.stackexchange.com/a/71355/21583 I included some background as to why I believed Spreadsheets worked that way.
Recently, as Rubén points out in a comment, Google Spreadsheets have changed, so that it now gives a proper error message instead of just timing out, when trying to do what the OP tried. As such, my answer no longer reflects reality, and there are now two other answers that are up-to-date.
Should I now delete my answer, as it is no longer valid, or is the background information it includes still useful for historic/general purposes?
And what is the best way to deal with obsolete answers in general?