sum of the first 5 prime numbers?
465400
2, 3, 5, 7, 11\n28\n\nFYI- 1 is not a prime number! It is only divisible by 1. To be a prime number, it must be divisible by 2 numbers.\n\nprime numbers up to 20-\n2, 3, 5, 7, 11, 13, 17, 19\n\nto find a prime number, start at the number 2. cross out every other number (that would be 4, 6, 8, even numbers). Then cross out every 3rd number, every 4th number, and so on. The remaining numbers are prime!\n\nHope this helps!
293052
2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97\n\n101 is the next prime number ... \nso 24 prime numbers between 1 - 100
249626
A prime number is a natural number greater than 1 that can be divided evenly only by 1 and itself. The first few prime numbers are\n\n2, 3, 5, 7, 11, 13, 17, 19, 23, 29, ...
598439
There are quite a few, 22 is the smallest such that there are exactly 3 ways. The ones less than one hundred are:\n\n22= 19+3 = 17+5 = 11+11\n24= 19+5 = 17+7 = 13+11\n26= 23+3 = 19+7 = 13+13\n30= 23+7 = 19+11 = 17+13\n40= 37+3 = 29+11 = 23+17\n44= 41+3 = 37+7 = 31+13\n52= 47+5 = 41+11 = 29+23\n56= 53+3 = 43+13 = 37+19\n62= 59+3 = 43+19 = 31+31\n98= 79+19 = 67+31 = 61+37\n\nOf course the more interesting question is Goldbach's Conjecture: Can every even number greater than 2 be expressed as the sum of 2 primes in at least one way? An interesting open problem.
628552
Use order ie\nParenthesis, Exponents, Division, Multiplication, Addition, Subtraction.\nThus, \n(4*5)+9-6 = (20)+9-6 = 29-6 = 23
30589
2(5)-5(5)+2(5)=\n10-25+10\n20-25\n-5
1139003
(n/(n - 3)) + (5/(2n - 6))\n(n/(n - 3)) + (5/(2(n - 3)))\nMultiply everything by 2(n - 3)\n(2n + 5)/(2n - 6)
90213
it isn't prime: it's divisible by 7 (which is one of my favourite numbers).\nIf you add it to 668^2 you get 669^2 (but that's a trick you can do with every odd number).
954148
3, 5, 7\n\nIn mathematics, a prime number (or a prime) is a natural number that has exactly two (distinct) natural number divisors, which are 1 and the prime number itself. There exists an infinitude of prime numbers, as demonstrated by Euclid in about 300 B.C.. The first 30 prime numbers are 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 101, 103, 107, 109, and 113 (sequence A000040 in OEIS); see the list of prime numbers for a longer list.\n\nThe property of being a prime is called primality, and the word prime is also used as an adjective. Since 2 is the only even prime number, the term odd prime refers to all prime numbers greater than 2.\n\nThe study of prime numbers is part of number theory, the branch of mathematics which encompasses the study of natural numbers. Prime numbers have been the subject of intense research, yet some fundamental questions, such as the Riemann hypothesis and the Goldbach conjecture, have been unresolved for more than a century. The problem of modelling the distribution of prime numbers is a popular subject of investigation for number theorists: when looking at individual numbers, the primes seem to be randomly distributed, but the "global" distribution of primes follows well-defined laws.\n\nThe notion of prime number has been generalized in many different branches of mathematics.
881616
The sum of the first n tetrahedral numbers is \n\nn(n+1)(n+2)(n+3)/4!\n\n(The sum of first n of these is in turn n(n+1)(n+2)(n+3)(n+4)/5!, and so on.)
403326
1+2+3+4+5+6+7+8+9/3+8*2-4\n=36+3+16-4\n=51
73101
1+5+10+25+50+100\n\n$1.91
28467
I just had a math packet dealing with this topic.  There are many equations out there that deal with finding primes, but all so far fail at a certain point in the sequence.  The method you refer to, called the Sieve of Eratosthenes, was developed by its namesake in Greece sometime between the 500s and 350 B.C. and is so far the only proven method to find primes.  Sorry, but unfortunately, there is no other accurate choice.
276262
You just have to list all the possible answers until you get 6 (your lowest number) in a row without skipping one.  After that you could get the next six by adding the 6 to those six.\n\nYou can get:  6, 11, 17, 18, 22, 23, 24, 28, 29, 30, 32, 33, 34, 35, 36, 38, 39, 40, 41, 42, 44, 45, 46, 47, 48, 50, 51, 52, 53, 54, 55.  There are 6 in a row.  So the highest you CAN'T get was 49.\n\nIt only works if the two numbers are relatively prime (they have no common factors besides 1).  The formula for finding the number is:\n\n(higher number) times (lower number minus 1) minus lower number\n\nHere that is 11(6-1) - 6 = 11(5) - 6 = 55-6 = 49
558121
i=i+2 (i=4)\ni++ (i=5)\ni=5
499816
Factor each number into their prime factors.\nTake the greatest number of occurrences of each\nprime and use them and only them  as the factors of your answer.\n\n  For example 4 and 10. Primes for each are 2,2 and\n2,5. 2 occurs at most two times and 5 occurs at most\nonce. So the factors in your answer are 2,2,5\nand the answer is 20. \n  Concise but complete. Exhaustive but exclusive.\nThat's elegance.
888908
The answer is 23475.\n\nLet's look at how I got there:\n\n\nThe first digit is a prime number:  2,3,5,7\n\nOne is not a prime, so anything starting with 1 is not actually an option.  There are two valid numbers, but one of them has repeating digits.\n\nGood.  That narrows it down a lot.\n\nThe third digit is twice the first digit:  Following from the numbers possible for the first digit, it's 4,6,10,or 14.  It obviously cannot be the last 2 since they are two digits.  That means it is either 4 or 6, and the first digit is 2 or 3.\n\nSo far we have\n2x4xx or\n3x6xx\n\nThe fourth digit is the third digit plus 3.  That's easy.  We now have\n2x47x or\n3x69x\n\nThe fifth digit is the difference between the first digit and the fourth digit.  7-2=5 and  9-3=6  We now have\n\n2x475 or\n3x696\n\nWait!  The second number has a repeated digit, 6.  It thus cannot be the number.\n\nLet's go on with option 1.  The second digit is the fifth digit minus the first digit.  5-2=3\n\nThe number is 23475.\n\n\nHope this helps.