The server sends the messages to all people in the channel, also back to the sender himself.
When every minute one person joins and says hi,
how many "hi" messages were totally sent for this channel after 0x4badc0ded minutes ?
No one ever leaves the channel, so there are 0x4badc0ded people at the end
Further explanation for 3 minutes:
1st person joins, sends hi, the server sends hi back to 1 persons.
2nd person joins, sends hi, the server sends hi back to 2 persons.
3rd person joins, sends hi, the server sends hi back to 3 persons.
Line 1: 2 messages sent
Line 2: 3 messages sent
Line 3: 4 messages sent
Adding these up means for 3 minutes are 9 messages sent.
how many "hi" messages were totally sent for this channel after 0x4badc0ded minutes ?