Irrational Numbers from Adjacent Natural Numbers (Part VIb)

A Sequence of Irrational Numbers Derived from2xy2 ∕ (x + y)

It has been shown (Between_two_Rational_Numbers on Wiki) that between two real numbers (ℝ) there exists an irrational number. Accordingly, it will be shown here that between two adjacent natural numbers (ℕ) there exists an irrational number (ℝ\ℚ). In addition, an arithmetic progression or sequence of irrational numbers will be generated in this section where the common difference (Δ) between the irrational numbers generated from 2xy2 ∕ (x + y). The inductive proof for this irrational equation is found in the previous section Part Vb. So, therefore, let's proceed as follows:

The sequence derived from the equation 2xy2 ∕ (x + y) is shown in Table I where the values of x and y range, respectively, from 1 to 12 and 2 to 13. The difference (Δ) between the irrational numbers is approximately 1.0 in the sequence, and approaches the value of 1 as x and y increase without bound. The value for each 2xy2 ∕ (x + y), is calculated to 6 decimal places, is irrational and each of these values indeed falls between their respective consecutive natural numbers. Table I shows the results where The third column heading SQRT is equal to 2xy2 ∕ (x + y). The last two rows shows data for large values of n, giving a Δ value close to one.

Table I Irrational (Sequence)
x y SQRTΔ
121.632993
232.6832821.050289
343.7032801.019998
454.7140451.010765
565.7207761.006731
676.7253821.003352
787.7287341.002549
898.7312831.002002
9109.7332851.001616
101110.7349011.001331
111211.7362321.001115
121312.737347
499500499.749687-
500501500.7496881.000001

The sequence can be written as one line sequence (for the first ten natural numbers, in red):

1, 1.632993, 2, 2.683282, 3, 3.703280, 4, 4.714045, 5, 5.720776, 6, 6.725382, 7, 7.728734, 8, 8.731283, 9, 9.733285, 10, 10.734901

Go back to Part Vb for proof by induction of 2xy2 ∕ (x + y).

Go to Part I or Part IV for non-staircase (ramp) methods. Go back to homepage.


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