Talk:Figurate number

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You mention that you can get the value of n^2 by adding up the first n odd integers, and that to get n^3 you use something similar to a moving average... Actually, it seems that there is a simple formula that can tell you what number to start at and at which number to end, for any power. To get n^a you start counting at n^(a-1)-(n-1) and end at n^(a-1)+(n-1). For example: 3^2 start at: 3^(2-1)-(3-1)=3-2=1 end at: 3^(2-1)+(3-1)=3+2=5 So 3^2 = 1+3+5=9

4^5 start at: 4^(5-1)-(4-1)=256-3=253 end at: 4^(5-1)-(4-1)=256+3=259 so 4^5 = 253+255+257+259=1024 This method has worked with every test I tried, but I could've missed something. 64.223.238.101 17:29, 5 Mar 2004 (UTC)

[edit] Wikipedia is not a textbook

Is there a shortcut? Can S be manipulated to generate fourth powers?

Wikipedia is an encyclopedia. It should not present exercises for the reader to solve; it should present the solution and explain it in detail. --Eequor 15:21, 27 May 2004 (UTC)

[edit] A topic related site

Greetings, I am the moderator for

[[1]]

where the topic of figurate numbers is open for discussion with hopes of finding answers to puzzles and practical applications for this fascinating field.

[edit] Question about the location of a paragraph

The paragraph "This procedure (taking many words to explain, but quickly executed) is not restricted to calculating square roots of natural numbers or positive integers. It can even be applied toward calculating the irrational square root of 2, to any number of decimal places." appears at the end of the section on "Cubes and cube roots" but it appears to belong to the discussion in the section on "Square roots". Is this intentional for some reason that I have not grasped?

You have a good point there. In fact, if they are going to talk about square roots and cube roots, they should also include the roots of triangles, pentagons, and if possible, tetrahedrons, etc; Aside from the use applied by children in grade school, others need to mention additional potential uses for figurate numbers. --R3hall (talk) 22:37, 4 May 2008 (UTC)R3hall —Preceding unsigned comment added by R3hall (talk • contribs) 13:22, 25 March 2008 (UTC)