Why is the induction step for the sum of the first n odd numbers unclear?
#1
I keep getting stuck trying to prove that the sum of the first n odd numbers is n². I understand the pattern works, but my induction step feels like I'm just forcing it algebraically without really seeing why it holds together.
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#2
I finally stopped trying to memorize the algebra and watched the numbers stack. Each new odd number you add is 2 more than the last, so the jump from n to n+1 is 2n+1. That difference is exactly the width of a new row if you think of a square. It clicked when I drew a square with n rows of dots.
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#3
I keep thinking maybe it's not about a slick induction so much as just seeing the pattern in visuals. The step felt like forced algebra until I tried a geometric view: a square of side n grows by a border of width 1, which adds 2n+1 items.
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#4
I doodled dots for n=1,2,3. 1, then 1+3=4, then 1+3+5=9. My brain wandered to triangular numbers for a minute, like thinking about how you stack shapes, then came back to how each new term is just the next odd count and how that lines up with squaring the side.
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#5
Do you maybe need a different angle—like a geometric interpretation?
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