# What would be the next number in the following sequence of numbers? 9,15,21

9-15-21-25-27-33-35-39-45-49-51-55-57-63-65-69-75-77-81-85-87-91-93-95-99-?-?-?-?-?

What are the next five numbers in this sequence?

Hint 1: This sequence can go on indefinitely

Hint 2: Based upon another sequence.

• – Beastly Gerbil Mar 8 '17 at 19:20
• The next number is obviously 1515. – Ian MacDonald Mar 8 '17 at 19:31
• OEIS has this sequence. – greenturtle3141 Mar 8 '17 at 19:53
• @BeastlyGerbil In what way did my original question differ from your model question. – GwenKillerby Mar 8 '17 at 20:27
• @GwenKillerby: It's not supposed to be a model, but a bad example. – M Oehm Mar 8 '17 at 20:28

105

and the sequence is

Odd nonprimes

• Did I make the sequence too long? – GwenKillerby Mar 8 '17 at 20:26
• @GwenKillerby Pretty much any bare OEIS sequence is a bad puzzle; such puzzles are uninteresting and, in many cases, are less an exercise in "deduce the pattern" and more one of "guess what sequence the poser was thinking of". Beastly Gerbil already pointed you at the post which mentions why these tend to make bad puzzles; maybe you should read it instead of challenging the helpful critique. – Rubio Mar 8 '17 at 21:00