Question 1085312
13,4,-11,-32
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13-4 = 9
4-15 = -11
from 9 to 15 = 6
-11-21 = -32
from 15 to 21 = 6
See the pattern? So:
-21-6 = -27, -32-27 = -59 this is your 5th number
-27-6 = -33; -59-33 = -92 this is your 6th number
For your info, this is a quadratic sequence.