Oddness with OO.o 2.4 and PDF export of .odt files with 'formula' objects in them:
sampleMath.pdf(no options checked in the export window)
'PDF/A-1' only checked
Another set: Numbers.odt and the PDF
Numbers2.odt(note plaintext vs objects) and the PDF and another with no changes to the document between exports other than file name [ignore the red upside down ? marks, that's just for symbols the formula engine doesn't understand]