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List the complementary / symetric prime couples
Problem statement For a given positive integer n, provide the prime couples (p,p') such that p + p' = 10^n. NB : a number li...

1 year ago

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Check Legendre's conjecture
Context and problem statement Legendre's conjecture states for a given positive integer n, there always exists at least one pri...

1 year ago

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List the twin prime couples
Problem statement The twin prime couples (p,p') are the ones such that p' = p + 2. For a given integer n > 1, list the twin p...

1 year ago

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Check p = 6n +/- 1, the generic formula for odd prime numbers greater than 3
Problem statement For all odd prime number p greater than 3, there exists a positive integer n, such that p = 6n +/- 1 : ...

1 year ago

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Check p = 4n +/- 1, the generic formula for odd prime numbers
Problem statement For all odd prime number p, there exists a positive integer n, such that p = 4n +/- 1 : Check this f...

1 year ago

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Chek the Delta = p' - p = 6k gap theorem about arithmetic progressions in the prime number set
Context In the prime numbers set there are some arithmetic progressions (sequences of three or more consecutive prime number...

1 year ago

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Find Logic 18

1 year ago

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Find Logic 12

1 year ago

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Find Logic 19

1 year ago

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List the near-square primes, p = n² + 1 (Landau's 4th problem)
Historical context At the 1912 International Congress of Mathematicians, Edmund Landau listed four basic problems about prime...

1 year ago

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List primes which are the sum of two consecutive lower primes plus minus one
Problem statement Some prime numbers can be written as the sum of two consecutive lower primes plus / minus one : Like t...

1 year ago

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area of an annulus
Given the diameter d of the inner circle of the annulus. Given length z of a chord of the outer circle of the annulus. This chor...

1 year ago

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Create a Multiplication table matrix...
Create a product table in this format: P = [ 1 2 3 4 5; 2 4 6 8 10; 3 6 9 12 15; 4 8 12 1...

1 year ago

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Estimating Monthly Electricity Cost for a Household Appliance
You recently bought an electric kettle for your kitchen, and you want to estimate how much it costs to run every month. The kett...

1 year ago

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Voltage Divider Calculation
A voltage divider is a simple circuit used to obtain a reduced voltage from a higher voltage source using two resistors in serie...

1 year ago

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LED Current Calculation
In an electrical circuit, the current (III) flowing through an LED is determined using Ohm’s Law: Where: I is the current ...

1 year ago

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Inductor Energy Storage Calculation
The energy (EEE) stored in an inductor is given by the formula: Where: E is the energy in joules (J) L is the inductance in...

1 year ago

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Calculate Charge Using Capacitance and Voltage
The charge (Q) stored in a capacitor is given by the formula:Q=C×V where: C is the capacitance (in farads) V is the voltage (...

1 year ago

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Energy Stored in a Capacitor
The energy (E) stored in a capacitor is given by the formula: where: C is the capacitance (in farads) V is the voltage (in ...

1 year ago

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Calculate Current in a Series Circuit Using KVL
Kirchhoff's Voltage Law (KVL) states that the sum of voltages around a closed loop is zero. Given a voltage source (V) and three...

1 year ago

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Calculating the Total Resistance in a Series Circuit
Description: In a series circuit, the total resistance is the sum of the individual resistances. This problem asks you to write ...

1 year ago

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Simple Electrical Power Calculation
Calculate the electrical power using the formula: P=V×I where: V is the voltage (in volts) I is the current (in amperes)

1 year ago

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Ohm’s Law - Calculate Resistance
Ohm’s Law states that resistance R can be calculated as:R=V/I where: V is the voltage (in volts) I is the current (in ampere...

1 year ago

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Stress-Strain Properties - 2
The resilience of a material is its ability to resist permanent (or plastic) deformation. The resilience coincides with the elas...

1 year ago

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Stress-Strain Properties - 1
This is the first in a series of problems regarding mechanics of materials, in particular, material properties drawn from stress...

1 year ago

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List the Moran numbers
The quotient of a Moran number and its digit sum is prime. For example, 117 and 481 are Moran numbers because 117/(1+1+7) is 13 ...

1 year ago

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Natural numbers in string form
Create a cell array of strings containing the first n natural numbers. Slightly harder than it seems like it should be. Exampl...

1 year ago

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Fix the last element of a cell array
Note: this is lifted directly from <http://www.mathworks.com/matlabcentral/answers/82825-puzzler-for-a-monday Puzzler for a Mond...

1 year ago

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Create a cell array out of a struct
Create a cell array out of a (single) struct with the fieldname in the first column and the value in the second column: in: ...

1 year ago

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String Array Basics, Part 1: Convert Cell Array to String Array; No Missing Values
<http://www.mathworks.com/help/matlab/characters-and-strings.html String array> and cell array are two types of containers for s...

1 year ago