Rep and Seq

Rep
rep(value,repeats)
it repeats the value the number of times indicated.

#Repeat the number 4 five times.
rep(4, 5)

## [1] 4 4 4 4 4

#Repeat the sequence of values 1-5, three times.
rep(1:5, 3)

##  [1] 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5

#Repeat the seasons twice.
seasons=c("spring"," summer", "fall"," winter")
rep(seasons, 2)

## [1] "spring"  " summer" "fall"    " winter" "spring"  " summer" "fall"   
## [8] " winter"

Seq
seq(from = value1, to = value2, by = step)
it creates a list of numbers between value1 to value2 with increments of step

#sequence from 1 to 10:
seq(from = 1, to = 10, by = 1)

##  [1]  1  2  3  4  5  6  7  8  9 10

#sequence from 0 to 20 by 2:
seq(from = 0, to = 20, by = 2)

##  [1]  0  2  4  6  8 10 12 14 16 18 20