Powershell break a long array into a array of array with length of N and repeat first element in sub arrays

How's this:

$bigList = ("Name","One","Two","Three","Four","Five","six","Seven","Eight","Nine","Ten","Eleven","Twelve","Thirteen")

$counter = [pscustomobject] @{ Value = 0 }
$groupSize = 5

$bigList[1..$biglist.count] |
    Group-Object -Property { [math]::Floor($counter.Value++ / $groupSize) } |
    foreach-object {
        $_.Group.Insert(0,$biglist[0])
        write-output $_
    }

Output:

Count Name                      Group                                                                                                                                                                                                      
----- ----                      -----                                                                                                                                                                                                      
    5 0                         {Name, One, Two, Three...}                                                                                                                                                                                 
    5 1                         {Name, six, Seven, Eight...}                                                                                                                                                                               
    3 2                         {Name, Eleven, Twelve, Thirteen}

This works by stripping out the first element ("Name") and sending the rest of the array through the group-object cmdlet. The resulting objects are modified in the foreach-object scriptblock by inserting the value from the first element of the big list into the group property. The modified object is re-written to the pipeline.

Assuming you want these in an list of arrays, you'd need to modify the code slightly:

$arrayList = $bigList[1..$biglist.count] |
    Group-Object -Property { [math]::Floor($counter.Value++ / $groupSize) } |
    ForEach-Object {
        $_.Group.Insert(0,$biglist[0])
        ,$_.group
    }

$arraylist | 
    % {
        write-host ( $_ -join "," )
    }

Here, we deliberately output only the group property of the groupinfo object that comes from group-object. In addition, we use the , operator to force powershell to output an individual array. If this is not done, we end up with a single array that is just like $biglist, but with extra instances of 'Name' every 5 elements. The final chunk of code outputs the contents of each element of $arrayList, concatenating with commas to demonstrate that we do indeed have an array of arrays:

Name,One,Two,Three,Four,Five
Name,six,Seven,Eight,Nine,Ten
Name,Eleven,Twelve,Thirteen