The first 25 prime numbers (all the prime numbers less than 100) are: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97 (sequence A000040 in the OEIS).
3 & 6 - LCM = 3. 3's multiples are 3, 6, 9,12, 16, etc. 6's multiples are 6, 12, 18, etc. therefore, the least common multiple is 6. GCF - 3's factors are 1, 3, and 6's factors 1, 2, 3. so the greatest common factor is 3.
