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G = {4; 8; 12; 16; 20; 24; 28; 32; 36; 40; 44; 48; 52; 56; 60; 64; 68; 72; 76; 80; 84; 88; 92; 96; 100; 104; ...}
F = {1; 4; 9; 16; 25; 36; 49; 64; 81; 100; ...}
So, according to the statement, it is desired:
G ∩ F - the intersection between the 2 sets, that is, which numbers are present simultaneously in the 2 sets....
Looking at the sets we conclude that
OBS: note that in truth G are the multiples of 4