Project Euler
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NumberName Math LevelStrandMath key wordsCS key wordsScratch?List compiled by Jim Town
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1Multiples of 3 and 56RPmultiples, common multiples, skip countfor loops, if statementsYes*
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2Even Fibonacci numbersMath I/Alg IF-IFrecursion, sequenceswhile loops, modulo, if statementYes*
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3Largest prime factor5OAprime factorslists, modulo, while, ifYes
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4Largest palindrome product5NBTplace valuewhile loops, if statementsYes
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5Smallest multiple5OAprime factors(not needed)Yes
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6Sum square difference6,8EE
square numbers, expressions with exponents
for loops Yes
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710001st prime4OAprime numbers
prime number generating algorithm
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8Largest product in a series4NBTproductlistsNot feasible
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9Special Pythagorean triplet8Gpythagorean theoremloops, if statementsYes
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10Summation of primes4OAsum, prime
prime number generating algorithm
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11Largest product in a grid4NBTproductmatrices, if statements, for loopsNot feasible
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12Highly divisible triangular number4OAfactorslists, moduloYes
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13Large sum5NBTaddition algorithm, place valuestringsNot feasible
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14Longest Collatz sequenceMath I/Alg IF-IFsequencesfor, while, if, moduloYes
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15Lattice pathsMath II/GeomS-CP (+)patterns, pascal's triangle, combinationsfactorialYes
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16Power digit sum6EEexponents, place valueexponentsAdapted version
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17Number letter counts5NBTplace valuemodulo, for, ifYes, but messy
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18Maximum path sum I5NBTsum search algorithmNot feasible
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19Counting Sundays2NBTcalendar math, skip countingtime and/or moduloYes
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20Factorial digit sum5NBTfactorial, sum, place valuefactorialAdapted version
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21Amicable numbers5NBTdivisors, amicable, sumloops, if statementsYes
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22Names scores4NBTproductsorting, text filesNot feasible
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23Non-abundant sums5NBTdivisors, abundant, sum
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24Lexicographic permutationsMath II/GeomS-CP (+)permutations
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251000-digit Fibonacci numberMath I/Alg IF-IFrecursion, sequenceswhile loops, strings
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26Reciprocal cycles7NSfractions, decimalsfor loops, if statements
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coefficients, absolute value, inequalities, primes
loops, if statementsYes
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30Digit fifth powers6EEexponents, sumloops, if statements
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31Coin sums
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32Pandigital products
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33Digit canceling fractions
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34Digit factorials
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35Circular primes
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36Double-base palindromes
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37Truncatable primes
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38Pandigital multiples
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39Integer right triangles8Gright triangles, pythagorean theoremlists, loops, if statementsYes
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40Champernowne's constant
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41Pandigital prime
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43Sub-string divisibility
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44Pentagon numbers
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Triangular, pentagonal, and hexagonal
Math I/Alg IF-IFfunction notationloops, lists, if statementsAdapted version
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46Goldbach's other conjecture
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47Distinct primes factors
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48Self powers
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49Prime permutations
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50Consecutive prime sum
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56
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60
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99Largeset ExponentialMath I/Alg IA-SSEexponential expressionsloops, if statements, file readNot Feasible