Arithmetic sequences

  • Small pepper seedlings in orange pots.
    problem

    Many Matildas

    Age
    11 to 14
    Challenge level
    1 out of 3

    MatildaMatildaMatil... What is the 1000th letter?

  • Maxagon
    problem

    Maxagon

    Age
    11 to 14
    Challenge level
    2 out of 3

    What's the greatest number of sides a polygon on a dotty grid could have?

  • Natural Sum
    problem

    Natural Sum

    Age
    14 to 16
    Challenge level
    1 out of 3

    The picture illustrates the sum 1 + 2 + 3 + 4 = (4 × 5)/2. Prove the general formula for the sum of the first n natural numbers and the formula for the sum of the cubes of the first n natural numbers.

  • Series Sums
    problem

    Series Sums

    Age
    14 to 16
    Challenge level
    3 out of 3

    Let S1 = 1 , S2 = 2 + 3, S3 = 4 + 5 + 6 ,........ Calculate S17.

  • Summats Clear
    problem

    Summats Clear

    Age
    16 to 18
    Challenge level
    1 out of 3

    Find the sum, f(n), of the first n terms of the sequence: 0, 1, 1, 2, 2, 3, 3........p, p, p +1, p + 1,..... Prove that f(a + b) - f(a - b) = ab.

  • Prime sequences
    problem

    Prime Sequences

    Age
    16 to 18
    Challenge level
    1 out of 3

    This group tasks allows you to search for arithmetic progressions in the prime numbers. How many of the challenges will you discover for yourself?

  • Speedy summations
    problem

    Speedy Summations

    Age
    16 to 18
    Challenge level
    1 out of 3

    Watch the video to see how to add together an arithmetic sequence of numbers efficiently.

  • Be reasonable
    problem

    Be Reasonable

    Age
    16 to 18
    Challenge level
    2 out of 3

    Prove that sqrt2, sqrt3 and sqrt5 cannot be terms of ANY arithmetic progression.

  • Polite Numbers
    problem

    Polite Numbers

    Age
    16 to 18
    Challenge level
    2 out of 3

    A polite number can be written as the sum of two or more consecutive positive integers, for example 8+9+10=27 is a polite number. Can you find some more polite, and impolite, numbers?