Irrational Numbers from Adjacent Natural Numbers (Part XIb)

A Staircase Sequence of Irrational Numbers from √(x + 1)y2n

This is a coninuation of the induction proof Part XIa for (x + 1)y2n.

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 there is a common difference (Δ) between the irrational numbers generated from Part XIa for (x + 1)y2n. So, therefore, let's proceed as follows:

The sequence derived from the equation (x + 1)y2n is shown in Tables I and II where the values of n range from 1 to 20, while those of x and y range, respectively, from 1 to 18 and 2 to 19. The difference (Δ) between the irrational numbers are, respectively, about 1.0 and approaches the value of 1 as x and y increase without bound. The value for each (x + 1)y2n, is calculated to 6 decimal places, is irrational and the value falls between two consecutive natural numbers. In addition, the sixth column heading is SQRT = (x + 1)y2n. he column header 1 ∕ n sums up all 1 ∕ n up to that particular n value.

Table I Irrational Sequence
n1 ∕ n 1 ∕ nx y SQRTΔ
30.33330.3333121.632993
40.25000.5833232.5989760.965083
50.20000.7833343.5777090.979633
60.16670.9500454.5643550.986646
70.14291.0929565.5549210.990566
80.12501.2179676.5479000.992980
90.11111.3290787.5424720.994572
100.10001.4290898.5381500.995677
110.09091.51999109.5346260.996476
120.08331.6032101110.5316990.997072
130.07691.6801111211.5292270.997529
140.07141.7516121312.5271130.997886
150.06671.8182131413.5252850.998172
160.06251.8807141514.5236880.998403
170.05881.9396151615.5222800.998592
180.05561.9951161716.5210300.998750
190.05262.0477171817.5199130.998883
200.05002.0977181918.5189090.998996

If the natural numbers are plotted on a grid vs 1 ∕ n (actually plotted in reverse, the zero value not shown). The following picture of a staircase, whose risers are composed of the harmonic sequence starting at one third (if zero were considered a natural number the first step level would be one half). The blue lines are the steps, the red stars the irrational values between the natural numbers and the orange lines are the risers of the staircase. In addition, the numbers on the vertical axis are from column three of Table I. The rational number adjacent to each step, 1 ∕ n, correponds to the level of each step in which n approaches zero as the sequence approaches infinity.

Picture of a staircase

Is still possible to write out the as one line sequence (for the first ten natural numbers, in red):

1, 1.632993, 2, 2.598076, 3, 3.577709, 4, 4.564355, 5, 5.554921, 6, 6.547900, 7, 7.542472, 8, 8.538150, 9, 9.534626, 10, 10.531699

Go back to Part XIa for proof by induction of (x + 1)y2n.

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


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