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Nov 30 2014 01:39pm
Quote (Beat @ Nov 30 2014 02:27pm)
let C0, C1, C2 .... be defined by the formulaCn= 2^n - 1 for all
integers n >(or equal to) 0. Show that this sequence satisfies the recurrence relation Ck= 2C(k-1)+ 1


Quote (Beat @ Nov 30 2014 02:31pm)
solution they give you

subsitute k and k-1 in place of n

Ck = 2^k -1
C(k-1) = 2^(k-1) -1
for all int k >(or equal to) 0

2Ck-1 + 1 = 2(2^(k-1) -1
=2^k -2 + 1
=2^k -1
=Ck


Bolded part is what I dont get
it says it was substituted from C(k-1) = 2^(k-1) -1
so was the 2 and the +1 just added so the right side would equal ck?

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Nov 30 2014 02:20pm
C_k = 2C_(k-1) + 1
and C_(k-1) = 2^(k-1) -1

therefore you get
C_k = 2[2^(k-1) -1] + 1
C_k = 2^k -2 + 1
C_k = 2^k - 1
C_k = C_k

This post was edited by cdexswzaq on Nov 30 2014 02:24pm
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