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6 replies to this topic

#1 superprismatic

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Posted 30 August 2011 - 11:55 PM

Find a simple closed form expression for
the alternating series of squares,
n2-(n-1)2+(n-2)2-(n-3)2+...+42-32+22-12.
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#2 bushindo

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Posted 31 August 2011 - 01:11 AM

Find a simple closed form expression for
the alternating series of squares,
n2-(n-1)2+(n-2)2-(n-3)2+...+42-32+22-12.


It should be equal to
Spoiler for spoiler

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#3 plainglazed

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Posted 31 August 2011 - 02:16 AM


It should be equal to

Spoiler for spoiler


Spoiler for

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#4 Mukul Verma

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Posted 31 August 2011 - 06:12 AM

Spoiler for The complete answer

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#5 Mukul Verma

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Posted 31 August 2011 - 07:20 AM

P.S. bushindo, perfectly right.
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#6 plainglazed

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Posted 31 August 2011 - 10:47 AM

DOH! caught me sp - nice one. and thanks for calling me out Mukul Verma. should have known better (not to get the answer but to have doubted bushindo).
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#7 dark_magician_92

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Posted 31 August 2011 - 05:38 PM

Spoiler for typo: again Spoiler error sorry
[/spoiler]

Edited by dark_magician_92, 31 August 2011 - 05:39 PM.

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