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Any number that isn't on the list of products in an infinitely large multiplication table (excluding the 1s lines) is a prime.
All numbers in the 2s column on the multiplication table end in the even numbers 2, 4, 6, 8, or 0.
first do 20 times 20 then double the answer
×12345678910111213141516171819201123456789101112131415161718192022468101214161820222426283032343638403369121518212427303336394245485154576044812162024283236404448525660646872768055101520253035404550556065707580859095100661218243036424854606672788490961021081141207714212835424956637077849198105112119126133140881624324048566472808896104112120128136144152160991827364554637281909910811712613514415316217118010102030405060708090100110120130140150160170180190200111122334455667788991101211321431541651761871982092201212243648607284961081201321441561681801922042162282401313263952657891104117130143156169182195208221234247260141428425670849811212614015416818219621022423825226628015153045607590105120135150165180195210225240255270285300161632486480961121281441601761922082242402562722883043201717345168851021191361531701872042212382552722893063233401818365472901081261441621801982162342522702883063243423601919385776951141331521711902092282472662853043233423613802020406080100120140160180200220240260280300320340360380400
Yes