Sjmarf@sh.itjust.works to People Twitter@sh.itjust.works · 1 day agoIt looks so wrongsh.itjust.worksimagemessage-square49fedilinkarrow-up1521arrow-down125
arrow-up1496arrow-down1imageIt looks so wrongsh.itjust.worksSjmarf@sh.itjust.works to People Twitter@sh.itjust.works · 1 day agomessage-square49fedilink
minus-squareElvith Ma'for@feddit.orglinkfedilinkarrow-up19·23 hours agoThe digit sum of 51 is 6, which is divisible by three. So 51 is also divisible by three. It’s not even hard to see that it’s not prime.
minus-squaresugar_in_your_tea@sh.itjust.workslinkfedilinkarrow-up10·edit-23 hours agoYup, my personal prime check is: Even? Ends in 5? Digits sum to 3? If it fails all three and it’s not an “obvious” prime (<20), then it’s prime enough for me.
minus-squareKnock_Knock_Lemmy_In@lemmy.worldlinkfedilinkarrow-up2·8 hours agoAlso Ends in 0, but that’s covered by 5 really.
minus-squaresugar_in_your_tea@sh.itjust.workslinkfedilinkarrow-up3·2 hours agoIt’s also covered by being even.
The digit sum of 51 is 6, which is divisible by three. So 51 is also divisible by three. It’s not even hard to see that it’s not prime.
Yup, my personal prime check is:
If it fails all three and it’s not an “obvious” prime (<20), then it’s prime enough for me.
Also
Ends in 0,
but that’s covered by 5 really.
It’s also covered by being even.