[78-L] Victor number puzzlement

[David Lennick]

The RCA Victor Request Catalog (1951) has a price list at the back and it lists 
a couple of numbering series I've never seen before..30000 and up (ten-inch 
purple label) and 37000 and up (10 inch purple label). Qu'est'ce que c'est? 
Also, it lists the post 1942 ten-inch popular black label series as "20-1400 
and up". Thought it started at 20-1500. Did they go back and use some lower 
numbers for a special series at one point?

dl