integer-sequences

Functional library for precise access to integer sequences such as prime numbers, square numbers, triangle numbers, etc

Intro

npm install --save integer-sequences

Functional library for precise access to integer sequences. Total unit test coverage. Cached access offers performance. For example:

const intseqs = require('integer-sequences')
intseqs.prime.sequenceMax(100000000)  // takes 1900ms - first call
intseqs.prime.sequenceMax(100000000)  // takes 25ms - second cached call

It makes use of Big.js to guarantee precision when working with big numbers.

Numeric arguments can be given as:

strings - e.g. intseqs.prime.isTerm('1000000')
Big.js objects - e.g. intseqs.prime.isTerm(Big('1000000')) or intseqs.prime.isTerm(Big(1000000))
numbers - e.g. intseqs.prime.isTerm(1000000)

Function return values are typically Big.js objects. To access a Big.js object value:

const intseqs = require('integer-sequences')
const bigObj = intseqs.prime.term(10)
const value = bigObj.toFixed()
console.log(value) // logs '29'

Misc functions

intseqs.getNumbersAsJson(max: number)  // Returns a list of numeric JSON objects

Example:

intseqs.getNumbersAsJson(7)

Returns:

[
  {number: 1, cube: Big(1), fibonacci: [Big(1), Big(2)], padovan: [Big(1), Big(2), Big(3)], prime: false, tetrahedron: Big(1), triangle: Big(1), square: Big(1)},
  {number: 2, cube: false, fibonacci: Big(3), padovan: [Big(4), Big(5)], prime: 1, tetrahedron: false, triangle: false, square: false},
  {number: 3, cube: false, fibonacci: Big(4), padovan: Big(6), prime: 2, tetrahedron: false, triangle: Big(2), square: false},
  {number: 4, cube: false, fibonacci: false, padovan: Big(7), prime: false, tetrahedron: Big(2), triangle: false, square: Big(2)},
  {number: 5, cube: false, fibonacci: Big(5), padovan: Big(8), prime: 3, tetrahedron: false, triangle: false, square: false},
  {number: 6, cube: false, fibonacci: false, padovan: false, prime: false, tetrahedron: false, triangle: Big(3), square: false},
  {number: 7, cube: false, fibonacci: false, padovan: Big(9), prime: 4, tetrahedron: false, triangle: false, square: false}
]

Prime values returned may be of type number for performance reasons.

intseqs.getNumberAsJson(n: number)  // Returns the nth numeric JSON object

Prime numbers - A000040

term - isTerm - isTermFast

Full support for primes upto Prime(6000000)=104395301 (partial support thereafter)

intseqs.prime.sequence(n: number)       // Returns a list of the first n terms in the sequence
intseqs.prime.sequenceMax(max: number)  // Returns a list of the first terms, all terms being <= max
intseqs.prime.term(n: number)           // Returns the nth term
intseqs.prime.isTerm(n: number)         // Returns x where n is the xth term or false where n is not a term
intseqs.prime.isTermFast(n: number)     // Returns a boolean, is n a term?

Cube numbers - A000578

term isTerm

intseqs.cube.sequence(n: number)
intseqs.cube.sequenceMax(max: number)
intseqs.cube.term(n: number)
intseqs.cube.isTerm(n: number)

Fibonacci numbers - A000045

term isTerm isTermFast

intseqs.fibonacci.sequence(n: number)
intseqs.fibonacci.sequenceMax(max: number)
intseqs.fibonacci.term(n: number)
intseqs.fibonacci.isTerm(n: number)
intseqs.fibonacci.isTermFast(n: number)

Padovan numbers - A134816

term isTerm

intseqs.padovan.sequence(n: number)
intseqs.padovan.sequenceMax(max: number)
intseqs.padovan.term(n: number)
intseqs.padovan.isTerm(n: number)

Square numbers - A000290

term isTerm

intseqs.square.sequence(n: number)
intseqs.square.sequenceMax(max: number)
intseqs.square.term(n: number)
intseqs.square.isTerm(n: number)

Tetrahedron numbers - A000292

term isTerm

intseqs.tetrahedron.sequence(n: number)
intseqs.tetrahedron.sequenceMax(max: number)
intseqs.tetrahedron.term(n: number)
intseqs.tetrahedron.isTerm(n: number)

Triangle numbers - A000217

term isTerm

intseqs.triangle.sequence(n: number)
intseqs.triangle.sequenceMax(max: number)
intseqs.triangle.term(n: number)
intseqs.triangle.isTerm(n: number)

Author says

People think I am religious but, to my mind, I just love Jesus! People think man-made religion is boring! So do I. Worse than that, man-made religion is destructive. Jesus himself warned against it.

What Jesus wants is relationship; to be your friend. This video explains it fairly well.

Remember, Jesus is alive, and you can be too if you believe in Him and leave your life of sin :)

For God so loved the world that he gave his one and only Son, that whoever believes in him shall not perish but have eternal life. For God did not send his Son into the world to condemn the world, but to save the world through him. Whoever believes in him is not condemned, but whoever does not believe stands condemned already because they have not believed in the name of God’s one and only Son.

John 3:16-18

"He is no fool who gives up what he cannot keep to gain that which he cannot lose" Jim Elliot

npm