# Can a triangular number be a prime number?

## Can a triangular number be a prime number?

So our conjecture might be that 3 is the only triangular number which is prime. the triangular numbers go in the order two odd, two even, two odd and so on. in every three numbers, the second and third numbers are divisible by 3.

## What is Prime triangular number?

A triangle with rows containing the numbers that begins with 1, ends with , and such that the sum of each two consecutive entries being a prime. Rows 2 to 6 are unique, (OEIS A051237) but there are multiple possibilities starting with row 7. For example, the two possibilities for row 7 are and .

What is the 3 triangle number?

No odd perfect numbers are known; hence, all known perfect numbers are triangular. For example, the third triangular number is (3 × 2 =) 6, the seventh is (7 × 4 =) 28, the 31st is (31 × 16 =) 496, and the 127th is (127 × 64 =)

What is the 28th triangle number?

List Of Triangular Numbers. 0, 1, 3, 6, 10, 15, 21, 28, 36, 45, 55, 66, 78, 91, 105, 120,136, 153, 171, 190, 210, 231, 253, 276, 300, 325, 351, 378, 406, 435, 465, 496, 528, 561, 595, 630, 666, 703, 741, 780, 820, 861, 903, 946, 990, 1035, 1081, 1128, 1176, 1225, 1275, 1326, 1378, 1431, and so on.

### What is the formula for finding triangular numbers?

Triangular numbers are a pattern of numbers that form equilateral triangles. The formula for calculating the nth triangular number is: T = (n)(n + 1) / 2.

### Why 1 is a triangular number?

A triangular number is a number that can be represented by a pattern of dots arranged in an equilateral triangle with the same number of dots on each side. The first triangular number is 1, the second is 3, the third is 6, the fourth 10, the fifth 15, and so on.

Is 42 a triangular number?

Answer: 42 is the triangular number in the given list.

How do you tell if a number is a triangular number?

A number is termed as triangular number if we can represent it in the form of triangular grid of points such that the points form an equilateral triangle and each row contains as many points as the row number, i.e., the first row has one point, second row has two points, third row has three points and so on.

#### How many prime numbers are also triangle numbers?

The only number that is triangle and prime is 3. The triangle numbers can be generated from T= 2n^2+/-n = (n) (2n+/-1) so that when n=1, triangle number 3 is generated, and when n=2, triangle numbers 6 and 10 are generated, etc.

Is there a list of all prime numbers?

List of Prime Numbers Sequence Prime Number 1 2 2 3 3 5 4 7

How are prime number rows divisible in pascals triangle?

I’ve figured that for every prime number row, all numbers on the row (except for the first and last numbers, which must be 1) are divisible by the row number. The row number is also the second or second last number in the row. The first row is row 0. (the row with a single 1) For example, row 7 contains 1, 7, 21, 35, 35, 21, 7, 1.

## Which is the correct formula for a triangular number?

A triangular number or triangle number counts the objects that can form an equilateral triangle. The nth triangle number is the number of dots composing a triangle with n dots on a side, and is equal to the sum of the n natural numbers from 1 to n. The general representation of a triangular number is Tn= 1 + 2 + 3 + 4 +…+ (n-2) + (n-1) + n,