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(2E,4E)-3-ethyl-6-ethynyl-7-methyldeca-2,4-dienenitrile

I have named this according to the numbering shown as
3-ethyl-6-(1-methylbutyl) oct-2,4-diene-7-ynenitrile.
But my book's answer key says
3-ethyl-6-ethynyl-7-methyl deca-2,4-dienenitrile
This means it has taken the triple bond as a side chain. But IUPAC rule says that the chain with maximum number of double and triple bond is taken even if it is shorter than a chain with lesser double or triple bonds. Which answer is correct and why, for the given example?

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    $\begingroup$ “But IUPAC rule says that the chain with maximum number of double and triple bond is taken even if it is shorter than a chain with lesser double or triple bonds.” Such a rule had been given in old recommendations that are now obsolete. According to current IUPAC recommendations, the first criterion to be considered in choosing a preferred parent acyclic chain is the length of the chain; unsaturation is now the second criterion. $\endgroup$ – Loong Dec 3 '17 at 15:44
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As Loong said, the up-to-date IUPAC recommendation stipulates that the chain with the longest continuous chain of carbon atoms should be the parent chain. For this reason, I would agree with your textbook's answer.

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    $\begingroup$ Can you back that up with some more details and cite the rules necessary to understand it. Otherwise it is just a restatement of a comment and not necessarily a real answer. $\endgroup$ – Martin - マーチン Dec 5 '17 at 5:32

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