Seven | 7 (Angielski)
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Definicja wiek 13 lat poziom 2
The seventh counting number, the fourth prime number, the first hexahedral number. It is the third Mersenne number and the second Mersenne prime. It has the property that 7!+1 is a square (only 4,5 and 7 have this property). Its Fermat quotient is a square (the only other number for which this is the case is 3). It is the third Lucky number. 7 colours are sufficient to colour any map on a torus. φ(7)=6, d(7)=2, σ(7)=8 .
Relacje
- Pojęcia ogólniejsze:
- (en) 0-9
- Pojęcie opiera się na:
- (en) Fermat quotient
- (en) Lucky number
- (en) Mersenne number
- (en) Mersenne prime
- (en) Seven colour theorem
- Pojęcia oparte na:
- (en) Heptagon
Ufundowana przez: EU Socrates Minerva, HeyMath!, Cambridge University Press