Soldato
2, 3, 7, 17, 39, ??
a) 58
b) 85
c) 65
d) 75
Also, how do you work out the answer?
a) 58
b) 85
c) 65
d) 75
Also, how do you work out the answer?
2, 3, 7, 17, 39, ??
2 -> 3 is multiplied by 2, subtract 1
3 -> 7 is multiplied by 2, add 1
7 -> 17 is multiplied by 2, add 3
17 -> 39 is multiplied by 2, add 5
so next one will be multiplied by 2, add 7 which is 85 as people have pointed out.
i dont think thats the correct explanation though as the first one doesnt fit.
It does if you change subtract 1 to add -1
......thats not how these things generally work.
i dont think thats the correct explanation though as the first one doesnt fit.
Of course it fits.
Xn+1 = 2 * Xn + 2(n-0.5) where X0 = 2
if you want to define it like that instead?
....and why not?
you add 2 more than the added to the previous number starting from -1