A google search brought up this Sweet Seedless Tomato.  Notice the fine print that says it may have immature seed. 

This is an interesting article to read. It says the Sweet Seedless Tomato (above) was first sold by Burpee.  So, maybe it is on their website. (I didn't look.)

It mentions Amish Paste. I have planted them, and my sister likes them for canning.  They are not seedless, but I would say they have less seeds than some varieties.  But they are not seedless.