It seems like there are some parts of the question that are incomplete or unclear, particularly in sections B, C, and D. I'll start by answering the clear portions of the question, and then you can provide more details or correct any parts that need clarification.

A. DESCRIBE EACH PATTERN FORMED AND FIND THE NEXT THREE TERMS

1. Sequence: 1, 5, 9, 13, 17, ...

   Pattern: This is an arithmetic sequence where each term increases by 4.

   • Common difference (d): 4

   Next three terms:

   • 21 (17 + 4)
   • 25 (21 + 4)
   • 29 (25 + 4)

2. Sequence: 1, 2, 4, 7, 11, 16, ...

   Pattern: This is an increasing sequence where the difference between consecutive terms increases by 1.

   • Differences: $1 \rightarrow 2 \rightarrow 3 \rightarrow 4 \rightarrow 5$

   Next three terms:

   • 22 (16 + 6)
   • 29 (22 + 7)
   • 37 (29 + 8)

3. Sequence: 2, -4, 8, -16, 32, ...

   Pattern: This is a geometric sequence where each term is multiplied by -2 to get the next term.

   • Common ratio (r): -2

   Next three terms:

   • -64 (32 × -2)
   • 128 (-64 × -2)
   • -256 (128 × -2)

4. Sequence: 50, 49, 47, 44, 40, 35, ...

   Pattern: This is an arithmetic sequence where each term decreases by an increasing difference.

   • Differences: -1, -2, -3, -4, -5

   Next three terms:

   • 29 (35 - 6)
   • 22 (29 - 7)
   • 14 (22 - 8)

B. WRITE THE FIRST FOUR TERMS OF EACH SEQUENCE GIVEN THE GENERAL TERM.

Since the general terms are missing, I’ll need you to provide the general formulas to proceed with this part.

C. FIND THE INDICATED TERM

Again, the specific sequences or general terms are incomplete here. If you provide the missing details, I can calculate the indicated terms for you.

D. FIND EACH INDICATED SUM

The series and the number of terms to sum are missing. If you provide that information, I can help find the sums.

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Would you like to clarify or complete the missing parts?

Follow-Up Questions:

1. Can you provide the general terms or formulas for part B?
2. What are the sequences or general terms to be used in part C?
3. Could you specify the series or terms for part D?
4. Do you need help with any other patterns or sequences?
5. Would you like more examples of arithmetic or geometric sequences?

Tip: When dealing with arithmetic sequences, remember that the common difference is constant, while in geometric sequences, the ratio between terms is constant.