We construct via linkage a 3-fold $X = X_{13} \cup X_4 \subset \bf{P}^7$, which is an arithmetically Gorenstein Calabi-Yau 3-fold of degree 17 in $\PP^7$. For an artinian reduction $A_F$, the quadratic part of the ideal $F^\perp$ is the ideal of a plane and a point $p$, and $F^\perp$ contains a family of ideals of six points in the plane and the fixed point $p$. We construct $X_{13}$ in a web of cubics in a P6, and $X_{4}$ as a quartic in a P4. In the construction the intersection $X\cup X'$ of a component $X$ with the other is an anticanonical divisor on $X$.
The Betti table is
$\phantom{WWWW} \begin{matrix} &0&1&2&3&4\\\text{total:}&1&11&20&11&1\\\text{0:}&1&\text{.}&\text{.}&\text{.}&\text{.}\\ \text{1:}&\text{.}&3&3&1&\text{.}\\\text{2:}&\text{.}&7&14&7&\text{.}\\\text{3:}&\text{.}&1&3& 3&\text{.}\\\text{4:}&\text{.}&\text{.}&\text{.}&\text{.}&1\\ \end{matrix} $
This variety $X \subset \PP^7$ has two components, $X_{13}$ in a $\PP^6$ linked to a $\PP^3$ in the cubic pfaffians of a 7x7 skew matrix, and $X_4$, a quartic 3-fold in a $\PP^4$. $X_{13}$ and $X_4$ intersect in a hyperplane section of $X_4$.
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We now choose a skew symmetric $7 \times 7$ matrix of linear forms in $U$ whose cubic pfaffians contain a $\PP^4$.
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The variety defined by the cubic pfaffians is a 4-fold, has degree 14, and contains the $\PP^4$.
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We take the residual of the $\PP^4$ in $Y_{14}$. This is a 4-fold of degree 13.
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We intersect this variety with the $\PP^4$, obtaining a quartic hypersurface $X_4$ in $\PP^4$.
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Let $X_{13}$ be the 3-fold which is the intersection of $Y_{13}$ with the hyperplane $y_0 = 0$.
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The union $X$ of $X_{13}$ and $X_4$ is a 3-fold of degree 17 in $\PP^7$, with Betti table of type [331]
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The intersection of $X_4$ and $X_{13}$ is a quartic surface in a $\PP^3$, which is a hyperplane section of $X_4$.
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