The Basics
Hidden Patterns
Algebra & Probability
History & Lore
Mathematical Identifies
100

This is the number located at the very top of the triangle (Row 0).

1

100

The sum of any row n is equal to this base raised to the power of n

2

100

This formula, which starts (x+y)^n), uses the triangle’s rows to find coefficients.

Binomial Theorem

100

Although named after Blaise Pascal, the triangle was studied centuries earlier in this country by mathematician Yang Hui.

China

100

If you square every number in Row (n) and add them up, you get the middle number of Row (2n).

Sum of Squares

200

To find a value in the triangle, you add this many numbers from the row directly above it.

two 

200

If you shade only the odd numbers in the triangle, you create this famous fractal.

Sierpiński Triangle

200

 In "n choose k" notation, the "n" represents this part of the triangle.

Row

200

This was the primary century during which Blaise Pascal lived and published his "Treatise on the Arithmetical Triangle."

17th Century

200

This "sports-themed" identity says the sum of a diagonal starting from a 1 equals the number below and to the left of the last term.

Hockey Stick Identify

300

This is the specific value of the 3rd number in Row 4 (1, 4, 6, 4, 1)

6

300

Summing the numbers along shallow diagonals of the triangle produces this famous sequence.

Fibonacci sequence

300

To find the coefficients for (x+y)^2), you would look at this specific row.

Row 2 (1, 2, 1)

300

Before it was "Pascal’s," Persian mathematicians referred to it as the triangle of this famous poet and scholar.

Omar Khayyam

300

According to this rule, the alternating sum of any row (e.g., (1 - 4 + 6 - 4 + 1) always equals this value.

Zero

400

Because the left side is a mirror image of the right, the triangle is said to have this geometric property.

symmetry

400

The second diagonal (1, 2, 3, 4...) contains the counting numbers, but the third diagonal (1, 3, 6, 10...) contains these types of numbers.

Triangular Numbers 

400

Pascal’s Triangle is often used to calculate these, which represent the number of ways to choose a subset from a larger set.

Combinations

400

Pascal originally developed the triangle to help solve problems related to this "vice" involving dice and coins.

Gambling.

400

This identity describes the relationship where any number in the triangle is the sum of the two numbers above it.

Pascal's Identity
500

Every row in the triangle begins and ends with this integer.

1

500

If the first number after the "1" in a row is this type of number, then every other number in that row (excluding the 1s) is divisible by it.

Prime Number

500

This is the coefficient of the (xy^{3}) term in the expansion of (x+y)^4).

4

500

This is the name of the rule stating that the sum of a diagonal of any length equals the number below the last entry but not in that diagonal.

Hockey Stick Identity

500

If you treat each row as digits (carrying over when numbers are (>9), Row (n) represents this number raised to the (n)th power.

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