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    can someone please tell me what the formulas are for these 7 sequences and also tell me how you got them:

    1)
    1, 5, 14, 30, 55

    2)
    1, 6, 18,40,75

    3)
    1, 7, 22, 50, 95

    4)
    1, 8, 26, 60, 115

    5)
    1, 9, 30, 70, 135

    6)
    1, 10, 34, 80, 155

    7)
    1, 11, 38, 90, 175

    thanks alot!
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    1) 1, 5, 14, 30, 55
    The 1st differences are,

    4, 9, 16, 25

    which are the squares of the first 4 (positive) integers greater than 1.
    So the sequence is given by,

    an = an-1 + n²

    The others are all solved identically. See here for how to.
 
 
 
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Updated: August 28, 2004
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