The numbers for which the process of summing up of the squares of its digits ends in 1 are happy numbers. On the other hand, numbers that don't end in 1 are called unhappy or sad numbers.
The first few unhappy numbers are 2, 3, 4, 5, 6, 8, 9, 11, 12, 14, 15, 16, 17, 18, 20, ... (OEIS A031177).
For example, starting with 7 gives the sequence 7, 49, 97, 130, 10, 1, so 7 is a happy number.
In number theory, a happy number is a number which eventually reaches 1 when replaced by the sum of the square of each digit. For instance, 13 is a happy number because , and . On the other hand, 4 is not a happy number because the sequence starting with and eventually reaches.
You might have also noticed that in addition to being a happy number, seven is also a prime number, which makes it the smallest happy prime number.
Detailed Solution. Hence, '15' is the correct answer.
In the U.S. the legal age for drinking, smoking, and entering nightclubs is 21. So the 21st birthday is a significant turning point for a young adult as they're now able to partake in more adult activities, legally.
Weird numbers are natural numbers that are abundant but not semiperfect. For example, 70 is the lowest weird number, because its set of proper divisors {1,2,5,7,10,14,35} sum to 74, but no subset of its set of proper divisors sum to the number 70, and 70 is the smallest number to meet such conditions.
Here are 10 Reasons that 10 is so important
Number ten symbolizes the completion of a cycle. Ten is the base of the decimal numeral system, by far the most common system of denoting numbers in both spoken and written language. The reason for the choice of ten is assumed to be that humans have ten fingers (digits).
We define a number as Lovely number if it repeats certain number twice in its binary representation and there is no other bit. For example, binary representation 10 is “ 1010” . As you can see 10 is repeating exactly twice, so it is a Lovely number. Another example, binary representation of 21 is “10101”.
The numbers for which the process of summing up of the squares of its digits ends in 1 are happy numbers. On the other hand, numbers that don't end in 1 are called unhappy or sad numbers. Let's look at the examples below to understand the concept behind it better. Example 1:- 23 is a happy number.
6174 is known as Kaprekar's constant after the Indian mathematician D. R. Kaprekar. This number is renowned for the following rule: Take any four-digit number, using at least two different digits (leading zeros are allowed).
The number 9 is powerful. It represents completion, although not a final ending—more like the fulfillment of one cycle so that you can prepare to initiate the next one. It's a recognition of life's ongoing ebb and flow.
The number seven was considered to be particularly interesting because it consisted of the union of the physical (number 4) with the spiritual (number 3). In Pythagorean numerology the number 7 means spirituality.
-digit vampires are 0, 7, 148, 3228, ... (OEIS A048935).
Over 30,000 people voted online for their favorite number, and the number chosen by the most people is… drum roll… 7! Almost half of all people chose numbers between 1 and 10.
According to the book Angel Numbers, by Kyle Gray, when you see 10:10 on a clock or elsewhere, it means “You are on the cusp of something miraculous. Trust that God and angels are one and are with you now.”
number symbolism
The number 12 is strongly associated with the heavens—the 12 months, the 12 signs of the zodiac, and the 12 stations of the Moon and of the Sun. The ancients recognized 12 main northern stars and 12 main southern stars.
The number 9 is revered in Hinduism and considered a complete, perfected and divine number because it represents the end of a cycle in the decimal system, which originated from the Indian subcontinent as early as 3000 BC.
The first few weird numbers are 70, 836, 4030, 5830, 7192, 7912, 9272, 10430, ... (OEIS A006037). An infinite number of weird numbers are known to exist, and the sequence of weird numbers has positive Schnirelmann density. (Sloane).
In magic. 1089 is widely used in magic tricks because it can be "produced" from any two three-digit numbers. This allows it to be used as the basis for a Magician's Choice.
Number Fun uniquely utilises the power of visualisation, animation, vocabulary, music, story and humour to help children learn mathematics in a brain-friendly way.
In Australia, turning 21 means one is an adult. The tradition means giving the person turning 21 a key to their family's house.
On the day you legally become an adult, you're allowed to purchase alcohol and cigarettes, gamble away your savings at the casino, apply for credit to buy a house, marry your high school sweetheart, and in Victoria, discover the freedom of mobility by getting your driver's license.
The number 19 in numerology represents spiritual growth and expansion. This number encourages you to reach for your goals and to dream big! It also represents faith, hope, and good luck. When you see this number, it is a reminder to stay positive and optimistic.