How to find a function for this set of numbers I found while working on the collatz conjecture?

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So, I was looking at the Collatz conjecture, and I thought of trying to reverse engineer the patterns in a certain sense, forming branches and trees. I figured it our for Branch-1, the formula, but Branch-2 is giving me trouble. It would be greatly helpful for me if one could help me find a formula to generate the values in the below table:

  1. 113
  2. 7253
  3. 464213
  4. 29709653
  5. 1901417813
  6. 121690740053
  7. 7788207363413
  8. 498445271258453
  9. 31900497360541013
  10. 2041631831074624853
  11. 130664437188775990613
  12. 8362523980081663399253
  13. 535201534725226457552213
  14. 34252898222414493283341653
  15. 2192185486234527570133865813
  16. 140299871119009764488567412053

I'll also share the formula for Branch-1 I got for this type of sequence.

$$3 + \sum_{n=0}^z 10 \cdot 4^k$$ $$z = (3n + 3) - 2$$ $$(n \in \mathbb W)$$

So something around these lines would be extremely helpful! I appreciate all the help, and I can try and calculate more values if needed.

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something that fits your previous sum: $113+\sum 7140\cdot 64^k$

EDIT: Your first sum can be written $53+\sum 3360\cdot 64^k$ and is also defined by $a_{n+1}=a_n*64+21$ but the way you want to write the second sum cannot be done the way you want (the $4^k$ sum comes from the sequence $5,341,21845,...$ that you see in Branch-1, but the sequence $11, 725, 46421,...$ which you see in Branch-2 does not produce this nice form)

The best I can do is $3+100\cdot4^z+\sum\limits_{k=0}^z10\cdot 4^k$ with $z=3n, n\geq 0$