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Number Sequence Solver

Identify patterns in number sequences and predict the next terms. Detects arithmetic, geometric, Fibonacci, prime, and other common sequences.

Enter numbers separated by spaces or commas

Common Sequences

Arithmetic

2, 5, 8, 11, 14...

Geometric

3, 6, 12, 24, 48...

Fibonacci

1, 1, 2, 3, 5, 8...

Squares

1, 4, 9, 16, 25...

Primes

2, 3, 5, 7, 11...

Triangular

1, 3, 6, 10, 15...

What is a Number Sequence?

A number sequence is an ordered list of numbers that follow a specific pattern or rule. Identifying the pattern allows you to predict future terms in the sequence.

Types of Sequences

Arithmetic Sequences

Each term differs from the previous by a constant amount (the common difference). Example: 3, 7, 11, 15, 19... (difference of 4)

Geometric Sequences

Each term is multiplied by a constant ratio. Example: 2, 6, 18, 54... (ratio of 3)

Fibonacci Sequence

Each term is the sum of the two preceding terms. Example: 1, 1, 2, 3, 5, 8, 13...

Quadratic Sequences

The second differences are constant. Example: 1, 4, 9, 16, 25... (squares)

Prime Numbers

Numbers only divisible by 1 and themselves. Example: 2, 3, 5, 7, 11, 13...

Sequences in Geocaching

Number sequences frequently appear in geocaching puzzles:

  • Coordinate puzzles: Find the pattern to get coordinates
  • Multi-caches: Each stage gives a number in a sequence
  • Missing terms: Fill in blanks to decode a message
  • Mathematical themes: Famous sequences like Fibonacci

How to Identify Patterns

  1. Calculate differences: Subtract consecutive terms
  2. Calculate ratios: Divide consecutive terms
  3. Check second differences: For quadratic patterns
  4. Look for famous sequences: Primes, Fibonacci, squares
  5. Try OEIS: The Online Encyclopedia of Integer Sequences

Tips for Solving

  • Enter at least 4-5 terms for better pattern detection
  • Check if numbers are special (primes, squares, etc.)
  • Multiple patterns may match short sequences
  • Consider letter-number conversions (A=1, B=2...)