fix math

docs/parallel.md

@@ -238,13 +238,13 @@ The functions described in this section of the manual include...
   `name` | Name of the multi-mesh adjacency object.
   `nmesh` | The number of mesh pieces in the corresponding multi-mesh object. This value must be identical in repeated calls to `DBPutMultimeshadj`.
   `mesh_types` | Integer array of length `nmesh` indicating the type of each mesh in the corresponding multi-mesh object. This array must be identical to that which is passed in the `DBPutMultimesh` call and in repeated calls to `DBPutMultimeshadj`.
-  `nneighbors` | Integer array of length `nmesh` indicating the number of `neighbors` for each mesh piece. This array must be identical in repeated calls to `DBPutMultimeshadj`.  In the argument descriptions to follow, let $S_k = \sum_{i=1}^k nneighbors[i]$, which sums the first `k` elements from the `nneighbors` array.
-  `neighbors` | Array of $S_nmesh$ integers enumerating for each mesh piece all other mesh pieces that neighbor it. Entries from index $S_k$ to index $S_{k+1}-1$ enumerate the `neighbors` of mesh piece `k`. This array must be identical in repeated calls to `DBPutMultimeshadj`.
-  `back` | Array of $S_nmesh$ integers enumerating for each mesh piece, the local index of that mesh piece in each of its `neighbors` lists of `neighbors`. Entries from index $S_k$ to index $S_{k+1}-1$ enumerate the local indices of mesh piece `k` in each of the `neighbors` of mesh piece `k`. This argument may be `NULL`. In any case, this array must be identical in repeated calls to `DBPutMultimeshadj`.
-  `nnodes` | Array of $S_nmesh$ integers indicating for each mesh piece, the number of nodes that it shares with each of its `neighbors`. Entries from index $S_k$ to index $S_{k+1}-1$ indicate the number of nodes that mesh piece k shares with each of its `neighbors`. This array must be identical in repeated calls to `DBPutMultimeshadj`. This argument may be `NULL`.
-  `nodelists` | Array of $S_nmesh$ pointers to arrays of integers. Entries from index $S_k$ to index $S_{k+1}-1$ enumerate the nodes that mesh piece `k` shares with each of its `neighbors`. The contents of a specific nodelist array depend on the types of meshes that are neighboring each other (See description below). `nodelists[m]` may be `NULL` even if `nnodes[m]` is non-zero. See below for a description of repeated calls to `DBPutMultimeshadj`. This argument must be `NULL` if `nnodes` is `NULL`.
-  `nzones` | Array of $S_nmesh$ integers indicating for each mesh piece, the number of zones that are adjacent with each of its `neighbors`. Entries from index $S_k$ to index $S_{k+1}-1$ indicate the number of zones that mesh piece `k` has adjacent to each of its `neighbors`. This array must be identical in repeated calls to `DBPutMultimeshadj`. This argument may be `NULL`.
-  `zonelists` | Array of $S_nmesh$ pointers to arrays of integers. Entries from index $S_k$ to index $S_{k+1}-1$ enumerate the zones that mesh piece `k` has adjacent with each of its `neighbors`. The contents of a specific zonelist array depend on the types of meshes that are neighboring each other (See description below). `zonelists[m]` may be `NULL` even if `nzones[m]` is non-zero. See below for a description of repeated calls to `DBPutMultimeshadj`. This argument must be `NULL` if `nzones` is `NULL`.
+  `nneighbors` | Integer array of length `nmesh` indicating the number of `neighbors` for each mesh piece. This array must be identical in repeated calls to `DBPutMultimeshadj`.  In the argument descriptions to follow, let $S_k = \sum_{i=1}^k \text{nneighbors}[i]$, which sums the first `k` elements from the `nneighbors` array.
+  `neighbors` | Array of $S_{\text{nmesh}}$ integers enumerating for each mesh piece all other mesh pieces that neighbor it. Entries from index $S_k$ to index $S_{k+1}-1$ enumerate the `neighbors` of mesh piece `k`. This array must be identical in repeated calls to `DBPutMultimeshadj`.
+  `back` | Array of $S_{\text{nmesh}}$ integers enumerating for each mesh piece, the local index of that mesh piece in each of its `neighbors` lists of `neighbors`. Entries from index $S_k$ to index $S_{k+1}-1$ enumerate the local indices of mesh piece `k` in each of the `neighbors` of mesh piece `k`. This argument may be `NULL`. In any case, this array must be identical in repeated calls to `DBPutMultimeshadj`.
+  `nnodes` | Array of $S_{\text{nmesh}}$ integers indicating for each mesh piece, the number of nodes that it shares with each of its `neighbors`. Entries from index $S_k$ to index $S_{k+1}-1$ indicate the number of nodes that mesh piece k shares with each of its `neighbors`. This array must be identical in repeated calls to `DBPutMultimeshadj`. This argument may be `NULL`.
+  `nodelists` | Array of $S_{\text{nmesh}}$ pointers to arrays of integers. Entries from index $S_k$ to index $S_{k+1}-1$ enumerate the nodes that mesh piece `k` shares with each of its `neighbors`. The contents of a specific nodelist array depend on the types of meshes that are neighboring each other (See description below). `nodelists[m]` may be `NULL` even if `nnodes[m]` is non-zero. See below for a description of repeated calls to `DBPutMultimeshadj`. This argument must be `NULL` if `nnodes` is `NULL`.
+  `nzones` | Array of $S_{\text{nmesh}}$ integers indicating for each mesh piece, the number of zones that are adjacent with each of its `neighbors`. Entries from index $S_k$ to index $S_{k+1}-1$ indicate the number of zones that mesh piece `k` has adjacent to each of its `neighbors`. This array must be identical in repeated calls to `DBPutMultimeshadj`. This argument may be `NULL`.
+  `zonelists` | Array of $S_{\text{nmesh}}$ pointers to arrays of integers. Entries from index $S_k$ to index $S_{k+1}-1$ enumerate the zones that mesh piece `k` has adjacent with each of its `neighbors`. The contents of a specific zonelist array depend on the types of meshes that are neighboring each other (See description below). `zonelists[m]` may be `NULL` even if `nzones[m]` is non-zero. See below for a description of repeated calls to `DBPutMultimeshadj`. This argument must be `NULL` if `nzones` is `NULL`.
   `optlist` | Pointer to an option list structure containing additional information to be included in the object written into the Silo file. Use a `NULL` if there are no options.
 
 * **Description:**