[填空题]
The barcode strings of a new product o0 g n3r-8olo v:.r8xhjkjo*o are creattmitstd-2sjffw g8i-v8b 3* + ed from four letters $ \mathrm{A}$, $\mathrm{B}$, $\mathrm{C}$, $\mathrm{D}$ and ten digits $0,1,2, \ldots, 9$ . No three of the letters may be written consecutively in a barcode string. There is no restriction on the order in which the numbers can be written. Find the number of different barcode strings that can be created.$\approx a \times 10^{b}$ a = b =