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Yes, because both statements are equivalent to the existence of an exact triangle of the form

$$W\longrightarrow X\oplus Y\oplus Z\longrightarrow V\longrightarrow\Sigma W.$$

The arrows are the same as in your diagram, except that you have to change of the sign of $W\rightarrow Y$ so that the first two arrows compose to $0$.

EDIT: The above 'answer' is shamely false. Let me just offer here a brief explanation of Jacob Lurie's correct answer. If the diagram is a homotopy colimit then we have an exact triangle

$$W\oplus W\stackrel{ \left(\begin{array}{cc} f&0\\ -g&g\\ 0&-h \end{array}\right) }\longrightarrow X\oplus Y\oplus Z\stackrel{(f',g',h')}\longrightarrow V\longrightarrow\Sigma W.$$$$W\oplus W\stackrel{ \left(\begin{array}{cc} f&0\\ -g&g\\ 0&-h \end{array}\right) }\longrightarrow X\oplus Y\oplus Z\stackrel{(f',g',h')}\longrightarrow V\longrightarrow\Sigma(W\oplus W).$$

The homotopy limit condition gives rise to an exact triangle of the form

$$W\stackrel{ \left(\begin{array}{c} f\\ g\\ h \end{array}\right) }\longrightarrow X\oplus Y\oplus Z\stackrel{\left(\begin{array}{cc} f'&-g'&0\\ 0&g'&-h' \end{array}\right)}\longrightarrow V\oplus V\longrightarrow\Sigma W.$$

If $W=X=Y=0$ then you get an exact triangle by putting $V=Z$ and $h'=1_Z$ $$0\longrightarrow Z\stackrel{1}\longrightarrow Z\longrightarrow 0$$

But if you put $X=Y=0$, $V=Z$, and $h'=1_Z$, then $W=\Sigma^{-1}Z$ since the exact triangle is

$$\Sigma^{-1}Z\stackrel{0}\longrightarrow Z\stackrel{\binom{0}{1}}\longrightarrow Z\oplus Z\stackrel{(1,0)}\longrightarrow Z.$$

Yes, because both statements are equivalent to the existence of an exact triangle of the form

$$W\longrightarrow X\oplus Y\oplus Z\longrightarrow V\longrightarrow\Sigma W.$$

The arrows are the same as in your diagram, except that you have to change of the sign of $W\rightarrow Y$ so that the first two arrows compose to $0$.

EDIT: The above 'answer' is shamely false. Let me just offer here a brief explanation of Jacob Lurie's correct answer. If the diagram is a homotopy colimit then we have an exact triangle

$$W\oplus W\stackrel{ \left(\begin{array}{cc} f&0\\ -g&g\\ 0&-h \end{array}\right) }\longrightarrow X\oplus Y\oplus Z\stackrel{(f',g',h')}\longrightarrow V\longrightarrow\Sigma W.$$

The homotopy limit condition gives rise to an exact triangle of the form

$$W\stackrel{ \left(\begin{array}{c} f\\ g\\ h \end{array}\right) }\longrightarrow X\oplus Y\oplus Z\stackrel{\left(\begin{array}{cc} f'&-g'&0\\ 0&g'&-h' \end{array}\right)}\longrightarrow V\oplus V\longrightarrow\Sigma W.$$

If $W=X=Y=0$ then you get an exact triangle by putting $V=Z$ and $h'=1_Z$ $$0\longrightarrow Z\stackrel{1}\longrightarrow Z\longrightarrow 0$$

But if you put $X=Y=0$, $V=Z$, and $h'=1_Z$, then $W=\Sigma^{-1}Z$ since the exact triangle is

$$\Sigma^{-1}Z\stackrel{0}\longrightarrow Z\stackrel{\binom{0}{1}}\longrightarrow Z\oplus Z\stackrel{(1,0)}\longrightarrow Z.$$

Yes, because both statements are equivalent to the existence of an exact triangle of the form

$$W\longrightarrow X\oplus Y\oplus Z\longrightarrow V\longrightarrow\Sigma W.$$

The arrows are the same as in your diagram, except that you have to change of the sign of $W\rightarrow Y$ so that the first two arrows compose to $0$.

EDIT: The above 'answer' is shamely false. Let me just offer here a brief explanation of Jacob Lurie's correct answer. If the diagram is a homotopy colimit then we have an exact triangle

$$W\oplus W\stackrel{ \left(\begin{array}{cc} f&0\\ -g&g\\ 0&-h \end{array}\right) }\longrightarrow X\oplus Y\oplus Z\stackrel{(f',g',h')}\longrightarrow V\longrightarrow\Sigma(W\oplus W).$$

The homotopy limit condition gives rise to an exact triangle of the form

$$W\stackrel{ \left(\begin{array}{c} f\\ g\\ h \end{array}\right) }\longrightarrow X\oplus Y\oplus Z\stackrel{\left(\begin{array}{cc} f'&-g'&0\\ 0&g'&-h' \end{array}\right)}\longrightarrow V\oplus V\longrightarrow\Sigma W.$$

If $W=X=Y=0$ then you get an exact triangle by putting $V=Z$ and $h'=1_Z$ $$0\longrightarrow Z\stackrel{1}\longrightarrow Z\longrightarrow 0$$

But if you put $X=Y=0$, $V=Z$, and $h'=1_Z$, then $W=\Sigma^{-1}Z$ since the exact triangle is

$$\Sigma^{-1}Z\stackrel{0}\longrightarrow Z\stackrel{\binom{0}{1}}\longrightarrow Z\oplus Z\stackrel{(1,0)}\longrightarrow Z.$$

correction of mistakes
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Fernando Muro
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Yes, because both statements are equivalent to the existence of an exact triangle of the form

$$W\longrightarrow X\oplus Y\oplus Z\longrightarrow V\longrightarrow\Sigma W.$$

The arrows are the same as in your diagram, except that you have to change of the sign of $W\rightarrow Y$ so that the first two arrows compose to $0$.

EDIT: The above 'answer' is shamely false. Let me just offer here a brief explanation of Jacob Lurie's correct answer. TheIf the diagram beingis a homotopy colimit is equivalent to the existence ofthen we have an exact triangle

$$W\oplus W\stackrel{ \left(\begin{array}{cc} f&0\\ -g&g\\ 0&-h \end{array}\right) }\longrightarrow X\oplus Y\oplus Z\stackrel{(f',g',h')}\longrightarrow V\longrightarrow\Sigma W.$$

The homotopy limit condition would dually translate in the existence ofgives rise to an exact triangle of the form

$$W\stackrel{ \left(\begin{array}{c} f\\ g\\ h \end{array}\right) }\longrightarrow X\oplus Y\oplus Z\stackrel{\left(\begin{array}{cc} f'&-g'&0\\ 0&g'&-h' \end{array}\right)}\longrightarrow V\oplus V\longrightarrow\Sigma W.$$

If $W=X=Y=0$ then you get an exact triangle by putting $V=Z$ and $h'=1_Z$ $$0\longrightarrow Z\stackrel{1}\longrightarrow Z\longrightarrow 0$$

But if you put $X=Y=0$, $V=Z$, and $h'=1_Z$, then $W=\Sigma^{-1}Z$ since the exact triangle is

$$\Sigma^{-1}Z\stackrel{0}\longrightarrow Z\stackrel{\binom{0}{1}}\longrightarrow Z\oplus Z\stackrel{(1,0)}\longrightarrow Z.$$

Yes, because both statements are equivalent to the existence of an exact triangle of the form

$$W\longrightarrow X\oplus Y\oplus Z\longrightarrow V\longrightarrow\Sigma W.$$

The arrows are the same as in your diagram, except that you have to change of the sign of $W\rightarrow Y$ so that the first two arrows compose to $0$.

EDIT: The above 'answer' is shamely false. Let me just offer here a brief explanation of Jacob Lurie's correct answer. The diagram being a homotopy colimit is equivalent to the existence of an exact triangle

$$W\oplus W\stackrel{ \left(\begin{array}{cc} f&0\\ -g&g\\ 0&-h \end{array}\right) }\longrightarrow X\oplus Y\oplus Z\stackrel{(f',g',h')}\longrightarrow V\longrightarrow\Sigma W.$$

The homotopy limit condition would dually translate in the existence of an exact triangle of the form

$$W\stackrel{ \left(\begin{array}{c} f\\ g\\ h \end{array}\right) }\longrightarrow X\oplus Y\oplus Z\stackrel{\left(\begin{array}{cc} f'&-g'&0\\ 0&g'&-h' \end{array}\right)}\longrightarrow V\oplus V\longrightarrow\Sigma W.$$

If $W=X=Y=0$ then you get an exact triangle by putting $V=Z$ and $h'=1_Z$ $$0\longrightarrow Z\stackrel{1}\longrightarrow Z\longrightarrow 0$$

But if you put $X=Y=0$, $V=Z$, and $h'=1_Z$, then $W=\Sigma^{-1}Z$ since the exact triangle is

$$\Sigma^{-1}Z\stackrel{0}\longrightarrow Z\stackrel{\binom{0}{1}}\longrightarrow Z\oplus Z\stackrel{(1,0)}\longrightarrow Z.$$

Yes, because both statements are equivalent to the existence of an exact triangle of the form

$$W\longrightarrow X\oplus Y\oplus Z\longrightarrow V\longrightarrow\Sigma W.$$

The arrows are the same as in your diagram, except that you have to change of the sign of $W\rightarrow Y$ so that the first two arrows compose to $0$.

EDIT: The above 'answer' is shamely false. Let me just offer here a brief explanation of Jacob Lurie's correct answer. If the diagram is a homotopy colimit then we have an exact triangle

$$W\oplus W\stackrel{ \left(\begin{array}{cc} f&0\\ -g&g\\ 0&-h \end{array}\right) }\longrightarrow X\oplus Y\oplus Z\stackrel{(f',g',h')}\longrightarrow V\longrightarrow\Sigma W.$$

The homotopy limit condition gives rise to an exact triangle of the form

$$W\stackrel{ \left(\begin{array}{c} f\\ g\\ h \end{array}\right) }\longrightarrow X\oplus Y\oplus Z\stackrel{\left(\begin{array}{cc} f'&-g'&0\\ 0&g'&-h' \end{array}\right)}\longrightarrow V\oplus V\longrightarrow\Sigma W.$$

If $W=X=Y=0$ then you get an exact triangle by putting $V=Z$ and $h'=1_Z$ $$0\longrightarrow Z\stackrel{1}\longrightarrow Z\longrightarrow 0$$

But if you put $X=Y=0$, $V=Z$, and $h'=1_Z$, then $W=\Sigma^{-1}Z$ since the exact triangle is

$$\Sigma^{-1}Z\stackrel{0}\longrightarrow Z\stackrel{\binom{0}{1}}\longrightarrow Z\oplus Z\stackrel{(1,0)}\longrightarrow Z.$$

correction of mistakes
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Fernando Muro
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Yes, because both statements are Yes, because both statements are equivalent to the existence of an exact triangle of the form

$$W\longrightarrow X\oplus Y\oplus Z\longrightarrow V\longrightarrow\Sigma W.$$

The arrows are the same as in your diagram, except that you have to change of the sign of $W\rightarrow Y$ so that the first two arrows compose to $0$.

EDIT: The above 'answer' is shamely false. Let me just offer here a brief explanation of Jacob Lurie's correct answer. The diagram being a homotopy colimit is equivalent to the existence of an exact triangle of the form

$$W\longrightarrow X\oplus Y\oplus Z\longrightarrow V\longrightarrow\Sigma W.$$$$W\oplus W\stackrel{ \left(\begin{array}{cc} f&0\\ -g&g\\ 0&-h \end{array}\right) }\longrightarrow X\oplus Y\oplus Z\stackrel{(f',g',h')}\longrightarrow V\longrightarrow\Sigma W.$$

The arrows are the same ashomotopy limit condition would dually translate in your diagram, except that you have to change of the signexistence of $W\rightarrow Y$ so thatan exact triangle of the first two arrows compose toform

$$W\stackrel{ \left(\begin{array}{c} f\\ g\\ h \end{array}\right) }\longrightarrow X\oplus Y\oplus Z\stackrel{\left(\begin{array}{cc} f'&-g'&0\\ 0&g'&-h' \end{array}\right)}\longrightarrow V\oplus V\longrightarrow\Sigma W.$$

If $0$.$W=X=Y=0$ then you get an exact triangle by putting $V=Z$ and $h'=1_Z$ $$0\longrightarrow Z\stackrel{1}\longrightarrow Z\longrightarrow 0$$

But if you put $X=Y=0$, $V=Z$, and $h'=1_Z$, then $W=\Sigma^{-1}Z$ since the exact triangle is

$$\Sigma^{-1}Z\stackrel{0}\longrightarrow Z\stackrel{\binom{0}{1}}\longrightarrow Z\oplus Z\stackrel{(1,0)}\longrightarrow Z.$$

Yes, because both statements are equivalent to the existence of an exact triangle of the form

$$W\longrightarrow X\oplus Y\oplus Z\longrightarrow V\longrightarrow\Sigma W.$$

The arrows are the same as in your diagram, except that you have to change of the sign of $W\rightarrow Y$ so that the first two arrows compose to $0$.

Yes, because both statements are equivalent to the existence of an exact triangle of the form

$$W\longrightarrow X\oplus Y\oplus Z\longrightarrow V\longrightarrow\Sigma W.$$

The arrows are the same as in your diagram, except that you have to change of the sign of $W\rightarrow Y$ so that the first two arrows compose to $0$.

EDIT: The above 'answer' is shamely false. Let me just offer here a brief explanation of Jacob Lurie's correct answer. The diagram being a homotopy colimit is equivalent to the existence of an exact triangle

$$W\oplus W\stackrel{ \left(\begin{array}{cc} f&0\\ -g&g\\ 0&-h \end{array}\right) }\longrightarrow X\oplus Y\oplus Z\stackrel{(f',g',h')}\longrightarrow V\longrightarrow\Sigma W.$$

The homotopy limit condition would dually translate in the existence of an exact triangle of the form

$$W\stackrel{ \left(\begin{array}{c} f\\ g\\ h \end{array}\right) }\longrightarrow X\oplus Y\oplus Z\stackrel{\left(\begin{array}{cc} f'&-g'&0\\ 0&g'&-h' \end{array}\right)}\longrightarrow V\oplus V\longrightarrow\Sigma W.$$

If $W=X=Y=0$ then you get an exact triangle by putting $V=Z$ and $h'=1_Z$ $$0\longrightarrow Z\stackrel{1}\longrightarrow Z\longrightarrow 0$$

But if you put $X=Y=0$, $V=Z$, and $h'=1_Z$, then $W=\Sigma^{-1}Z$ since the exact triangle is

$$\Sigma^{-1}Z\stackrel{0}\longrightarrow Z\stackrel{\binom{0}{1}}\longrightarrow Z\oplus Z\stackrel{(1,0)}\longrightarrow Z.$$

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Fernando Muro
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