Here is the sitemaps available for blogger :
if you have more than one post : URL/atom.xml?redirect=false&start-index=1&max-results=100
if if you have more than 100 post : URL/atom.xml?redirect=false&start-index=101&max-results=100
if you have more than 200 post : URL/atom.xml?redirect=false&start-index=201&max-results=100
Change the ??start-index=101 to 201, 202, 203, 204, 205.... and keep going
Hope this is the best answer to your question :)