The first 3 COMMON multiples of 17 will depend upon the OTHER NUMBER(S) with which 17 has common multiples. However, they will be regularly spaced within the multiples of 17.eg the first 3 COMMON multiples of:1 and 17 are 17, 34, 51;2 and 17 are: 34, 68, 102;5 and 17 are: 85, 170, 255;17 and 34 are: 34, 68, 102etc.
170 because 17 is prime
221, 442, 663
17, 34, 51, 68, 85, 102, 119, 136, 153, 170.
The first 3 multiples of 17 are: 17, 34, 51
I think you mean some common multiples. Since 17 is prime, there are no common factors of 17 and 21. Now the first common multiple will be 21x17. You can use more 21s or more 17s to find additional multiples. Here is one 17x21x21 Here is another 17x17x21
306
The GCF is 17.
51
The lowest common multiple of 13 and 17 is 221
The only Least Common Multiple (LCM) for 17 16 is 272.
Any multiple of 85.