# Do you know its property? (4)

**Algebra**Level 5

If \(t_{n}=8+ 6\binom{n-1}{1}+2\binom{n-1}{2}\), then find the digit sum of \[\displaystyle \large\sum_{n=1}^{1729} (t_{n}).\]

**Details and Assumptions:**

\(\binom{n}{r}=\dfrac{n!}{r! \times (n-r)!}\).

Digit sum refers to the sum of the digits of the number. For instance, Digit sum of 1729 is 1+7+2+9=19.

Assume \(\binom{n}{r}=0\)

**if**\(n<r\).