0
0
0

net - choose a jigsaw puzzle to solve

In mathematics, more specifically in general topology and related branches, a net or Moore–Smith sequence is a generalization of the notion of a sequence. In essence, a sequence is a function with domain the natural numbers, and in the context of topology, the codomain of this function is usually any topological space. However, in the context of topology, sequences do not fully encode all information about a function between topological spaces. In particular, the following two conditions are not equivalent in general for a map f between topological spaces X and Y: The map f is continuous (in the topological sense) Given any point x in X, and any sequence in X converging to x, the composition of f with this sequence converges to f(x) (continuous in the sequential sense) It is true, however, that condition 1 implies condition 2. The difficulty encountered when attempting to prove that condition 2 implies condition 1 lies in the fact that topological spaces are, in general, not first-countable. If the first-countability axiom were imposed on the topological spaces in question, the two above conditions would be equivalent. In particular, the two conditions are equivalent for metric spaces. The purpose of the concept of a net, first introduced by E. H. Moore and H. L. Smith in 1922, is to generalize the notion of a sequence so as to confirm the equivalence of the conditions (with "sequence" being replaced by "net" in condition 2). In particular, rather than being defined on a countable linearly ordered set, a net is defined on an arbitrary directed set. In particular, this allows theorems similar to that asserting the equivalence of condition 1 and condition 2, to hold in the context of topological spaces that do not necessarily have a countable or linearly ordered neighbourhood basis around a point.
Parkan in plants - Parkan in plants
Play now!
Parkan in plants

Added 2 months ago by Mila

46

M.Ś. Russia 2018 - colorful jigsaw puzzle
Play now!
M.Ś. Russia 2018

Added year ago by andi

17

M.Ś. Russia 2018 - colorful jigsaw puzzle
Play now!
M.Ś. Russia 2018

Added year ago by andi

10

"Soccer Friends" - Combine the pieces of the puzzle correctly to form the whole image
Play now!
"Soccer Friends"

Added year ago by Mirella

48

"Soccer Friends" - Combine the pieces of the puzzle correctly to form the whole image
Play now!
"Soccer Friends"

Added year ago by Mirella

32

For the patient - complicated puzzle
Play now!
For the patient

Added year ago by andi

26

Jigsaw puzzle - complicated puzzle
Play now!
Jigsaw puzzle

Added year ago by andi

11

Jigsaw puzzle - complicated puzzle
Play now!
Jigsaw puzzle

Added year ago by andi

28

Abstraction - complicated puzzle
Play now!
Abstraction

Added year ago by andi

30

Abstraction - abstract puzzle-2
Play now!
Abstraction

Added year ago by andi

9

polbesan - team trova l'athlete team trova l'athlete team trova l'athlete team trova l'atle
Play now!
polbesan

Added year ago by pol

21

Łukaszlorek1 - our beloved footballer, goalkeeper.
Play now!
Łukaszlorek1

Added year ago by Łukaszek

16 1

Football - Team game, the most popular sports discipline with about 4 billion fans around the world. Sport is h
Play now!
Football

Added over a year ago by Mateusz

80 1

cztery rakiety - kolorowe cztery rakiety
Play now!
cztery rakiety

Added over a year ago by Basieńka

101

lekkoatletyka - rzut dyskiem z koła
Play now!
lekkoatletyka

Added over a year ago by Romina

13

lekkoatletyka - pięć kółek olimpijskich
Play now!
lekkoatletyka

Added over a year ago by Rozalinda

57

podlewam poziomki - chłopiec podlewa poziomki
Play now!
podlewam poziomki

Added over a year ago by Regina

17

H2O wystarczy kropla - H2O wystarczy kropla
Play now!
H2O wystarczy kropla

Added over a year ago by Julia

22

tenis stołowy - stół, rakietka, piłeczka
Play now!
tenis stołowy

Added over a year ago by Basieńka

77

serwetka - zrobiona na szydełku
Play now!
serwetka

Added over a year ago by Halinka

49

Leon Thomas III - Leon Thomas III podczas sesji zdjęciowej.
Play now!
Leon Thomas III

Added over a year ago by Cat Valentine

10

Winx Club - Winx Club : Tecna Transformacja  Enchantix
Play now!
Winx Club

Added over a year ago by Natalia Wolanin

43

Sport to zdrowie - Siatkówka plażowa w modzie
Play now!
Sport to zdrowie

Added over a year ago by Iwona

10

campo da calcio - campo da calcio campo da calcio
Play now!
campo da calcio

Added over a year ago by Danilo Nussio

219

Dziewczyna anime - Ładna dziewczyna z ciemnymi włosami
Play now!
Dziewczyna anime

Added over a year ago by Weronika

4

sala gimnastyczna pg4 opole - opole sala gimnastyczna pg 4
Play now!
sala gimnastyczna pg4 opole

Added over a year ago by batek

98

M jak miłość Tvp2 - M jak miłość Tvp2
Play now!
M jak miłość Tvp2

Added over a year ago by Kinga

96

M jak miłość Tvp2 - M jak miłość Tvp2
Play now!
M jak miłość Tvp2

Added over a year ago by Kinga

92