HaLeivi: I must have gotten the daf wrong. There is a gemara on an amud beis in the 8th perek of bava basra that has the whole shtickle about 4 things lo hayu v’lo asid lihyos etc. and on tanna says “but there was a ben sorer umoreh, I sat on his matzeva and ate.” I have to look the daf up now.
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