1 + 2 + 3 + 4 + ... + 2020

is gelijk aan 		A.  \(C^2_{2019}\)
B.  \(C^2_{2020}\)
C.  \(C^2_{2021}\)
D.  \(C^2_{2021}\)
E.  \(V^2_{2020}\)
A    B    C    D    E

[ 6-5172 - op net sinds 11.7.2020-(E)-6.8.2024 ]

Translation in   E N G L I S H

IN CONSTRUCTION

Oplossing - Solution

1 + 2 + 3 + 4 + ... + 2020 = ½.2020.2021
C20212 = 2021.2020 /2
gricha