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Tănase Sofia

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5th centered triangular number: 31, Sofia

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5th centered triangular number: 31, Sofia

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Define a recurrence relation to obtain the successor:

a) a triangular number;

b) a square number;

c) a pentagonal number;

d) a polygonal number of order m

and calculate the first ten numbers of each order.

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1, 5, 12, 22, ...

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Proca Daniela

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Șarpe David

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Rudenco Polina

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Ciobu Vladimir

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Andoni Ana-Maria

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Melnic Nichita

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Free online apps bundle from GeoGebra: get graphing, geometry, algebra, 3D, statistics, probability, all in one tool!

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https://www.geogebra.org/classic/jgjbn5ef

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Free online apps bundle from GeoGebra: get graphing, geometry, algebra, 3D, statistics, probability, all in one tool!

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Mîndrilă Cristian

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Polygonal numbers can be triangle ones, square ones...

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Polygonal numbers can be triangle ones, square ones...

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Here are some presentation, with n= 4

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Centrated Triangular Numbers / Sevginur D-Etiler

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Centrated Triangular Numbers / Sevginur D-Etiler

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Free online apps bundle from GeoGebra: get graphing, geometry, algebra, 3D, statistics, probability, all in one tool!

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Free online apps bundle from GeoGebra: get graphing, geometry, algebra, 3D, statistics, probability, all in one tool!

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When you multiply an integer times itself, the resulting product is called a square number, or a perfect square.

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A pentagonal number is a figurate number that extends the concept of triangular and square numbers to the pentagon.

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A triangular number or triangle number counts objects arranged in an equilateral triangle.

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A polygonal number is a number that counts dots arranged in the shape of a regular polygon

We have worked on these numbers in the classroom.

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In class we have worked on triangular numbers, understanding the formula on how they are generated and drawing the first triangular numbers.

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The sequence of triangular numbers, starting with the 0th triangular number, is

0, 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, 66, 78, 91, 105...

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Polygonal numbers were first studied during the 6th century BC by the Ancient Greeks, who investigated and discussed properties of rectangular, triangular, and square numbers.