Question

True or False?
The recursive definition of the set S={1,5,9,13,17,…} is 1∈S;x∈S→x+4∈S.

Answer 1

Screenshot:
http://prntscr.com/57m71r

Answer 2

false

Answer 3

False

Answer 4

Why it's false?
I think it's True.
Both of "x" and "4" is a part of the set "S" so:
x+4=??
Replace any number of the set with "x":
1+4=5
or
5+4=9
or etc
all belong to the set "S" so it's True
@nbandy0128 @Saquara

Answer 5

@e.mccormick @jim_thompson5910
Can anyone please confirm the answer?

Answer 6

That looks right, but I'm not familiar with this notation. So I'd get a 2nd opinion.

Answer 7

@jim_thompson5910
What's your opinion please, true or false?
I am confused

Answer 8

it looks true, but again not 100% sure