**ERIC Number:**EJ1017613

**Record Type:**Journal

**Publication Date:**2013-Sep

**Pages:**1

**Abstractor:**As Provided

**ISBN:**N/A

**ISSN:**ISSN-0746-8342

**EISSN:**N/A

Proof without Words: Squares Modulo 3

Nelsen, Roger B.

College Mathematics Journal, v44 n4 p283 Sep 2013

Using the fact that the sum of the first n odd numbers is n[superscript 2], we show visually that n[superscript 2] is the same as 0 (mod 3) when n is the same as 0 (mod 3), and n[superscript 2] is the same as 1 (mod 3) when n is the same as plus or minus 1 (mod 3).

Descriptors: College Mathematics, Mathematics Instruction, Mathematical Logic, Validity, Mathematical Concepts, Equations (Mathematics)

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**Publication Type:**Reports - Descriptive; Journal Articles

**Education Level:**Higher Education; Postsecondary Education

**Audience:**N/A

**Language:**English

**Sponsor:**N/A

**Authoring Institution:**N/A

**Grant or Contract Numbers:**N/A