code:

function get-nested-groups {
    Param(
        [Parameter(Mandatory=$true)]$Identity
    )
    $entity = Get-ADObject -Identity $Identity
    $dn = $entity.DistinguishedName
    $groups = Get-ADGroup -LDAPFilter ("(&(objectClass=group)(member:={0}))" -f $dn)
    return $groups
}

$relations_list = New-Object System.Collections.ArrayList

function recurse-groups {
    Param(
        [Parameter(Mandatory=$true)]$Identity
    )
    foreach ($nested_group in get-nested-groups -Identity $Identity) {
        [void]$relations_list.add(("`"{0}`" -> `"{1}`"" -f $Identity.Name, $nested_group.Name))
        recurse-groups -Identity $nested_group
    }
}

$entity = Get-ADUser 'YOURNAMEHERE'
recurse-groups -Identity $entity

Write-Output (
@"
digraph G {{
rankdir=LR
"{0}" [shape=diamond]
{1}
}}
"@ -f ($entity.SamAccountName),($relations_list -join "`n")
)