I wrote -

> <xsl:template match='x'>
> <w>
> 	<xsl:copy-of select='.'/>
> 	<xsl:copy-of select='following-sibling::x[$modulus >
> position()]'/>
> </w>
> </xsl:template>

I wrote it this way to illustrate the point, but it could have been even
simpler -

<xsl:template match='x'>
 <w>
 	<xsl:copy-of 
        select='following-sibling::x[$modulus >= position()]'/>
 </w>
</xsl:template>

Cheers,

Tom P

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