Syntax Error trying to write a formula into a cell with VBA的问题是，无法直接添加换行符，需要将公式拆分成多个字符串，并使用&符号将它们连接起来。换行符需要使用_在行尾进行连接。

解决方法是创建一个函数，可以根据州名列表生成公式。首先创建一个存储州名的数组(ListOfStates)，然后使用Join函数将所有块通过&连接起来，最后将生成的公式赋值给指定的单元格。

代码如下：

Option Explicit
Public Sub Example()
    Dim ListOfStates() As Variant
    ListOfStates = Array("California", "Florida", "Texas", "New Mexico", "Alaska", "New Jersey", "Marikina", "Maryland", "Nebraska", "Pennsylvania", "Illinois", "Colorado", "Louisiana", "Idaho", "Hawaii", "Vermont", "West Virginia", "Connecticut")
    Range("D2").FormulaR1C1 = "=" & Join(CreateFormulaBlocks(ListOfStates), "&") 'join all blocks by &
End Sub
' returns an array of all blocks (each 6 states)
'
Public Function CreateFormulaBlocks(ByVal ListOfStates As Variant, Optional ByVal MaxPerBlock As Long = 6) As Variant
    ' how many blocks do we need
    Dim MaxBlocks As Long
    MaxBlocks = (UBound(ListOfStates) + 1) \ 6  ' note this is no normal division / but an integer division \
    ' create array for blocks
    Dim ReturnBlocks() As Variant
    ReDim ReturnBlocks(MaxBlocks - 1) As Variant
    ' create blocks
    Dim iBlock As Long
    For iBlock = 0 To MaxBlocks - 1
        Dim BlockStates() As Variant
        ReDim BlockStates(MaxPerBlock - 1) As Variant
        Dim iState As Long
        For iState = 0 To MaxPerBlock - 1
            BlockStates(iState) = ListOfStates(iBlock * 6 + iState)
        Next iState
        ' create one block of 6 states
        ReturnBlocks(iBlock) = CreateFromulaBlock(BlockStates)
    Next iBlock
    ' return all blocks as array
    CreateFormulaBlocks = ReturnBlocks
End Function
' returns one block of 6 states
' eg IF(ISNUMBER(SEARCH("California",RC[-2],1)),"California", IF(ISNUMBER(SEARCH("Florida",RC[-2],1)),"Florida", IF(ISNUMBER(SEARCH("Texas",RC[-2],1)),"Texas", IF(ISNUMBER(SEARCH("New Mexico",RC[-2],1)),"New Mexico", IF(ISNUMBER(SEARCH("Alaska",RC[-2],1)),"Alaska", IF(ISNUMBER(SEARCH("New Jersey",RC[-2],1)),"New Jersey", ""))))))
'
Public Function CreateFromulaBlock(ByVal States As Variant) As String
    Dim FormulaString As String
    Dim State As Variant
    For Each State In States
        FormulaString = FormulaString & "IF(ISNUMBER(SEARCH(""" & State & """,RC[-2],1)),""" & State & """, "
    Next State
    CreateFromulaBlock = FormulaString & """""" & String(UBound(States) + 1, ")")
End Function

这样可以解决问题。但是需要注意，如果在代码中添加太多的行连接符" _"，会出现"Too many line continuations"错误。这是因为VBA对行连接符的数量有限制。为了避免这个问题，可以使用上述的函数生成公式，只需将州名添加到列表中即可。