Estimated standard error of the mean (easy points for the answer)

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Trying to wrap my mind around the intuition of the standard error of the mean is the mission.

I was trying to make a really basic example with simple number to give myself more a sense of what is going on. I take three random sample experimentally. The probability in the population is the same.

s=(sample)
s1: 5, 6, 10, 20, 29
s2: 5, 6, 6, 11, 32
s3: 5, 7, 27, 29, 30

If you make the calculation we should obtain:

m=(mean)
m1: 14
m2: 12
m3: 19,6

v=(variance)
v1 84,4

sd=(standard deviation)
sd1: 9,18
sd2: 10,21
sd3: 11,19

Now,
se=(standard error)
using this formula: $$\frac{σ^{2}}{N}$$ se1 = 84,4 / 5 = 16,8

or this formula $$\frac{σ}{√N}$$ se1 = 9,18 / 2,23 = 4,11

Shouldn't the two formula be equal and give the same result?