PYHIYP means: Put your hands in your pockets i.e. use no calculators, no pen & paper; just your eyes and you brain.

The 1st task, a harbinger to be followed by many others, is to prove just by observation and common sense that none of the four numbers listed below is a prime.

i. 5,234,567,896,743
ii. 1,438,525,775,258,341
iii. 77,112,356,378,491
iv. 1,431,436,216,211,339

No time limit!
No cheating!
KISS!
Post your conclusions.

i. 5234567896743=3*1744855965581

Posted by Math Man on 2019-12-21 20:09:02