Tribonacci

Compute the nth Tribonacci number.

The Tribonacci numbers are the integer sequence

The sequence is defined by the recurrence relation

with seed values F_0 = 0, F_1 = 0, and F_2 = 1.

Installation

npm install @stdlib/math-base-special-tribonacci

Usage

var tribonacci = require( '@stdlib/math-base-special-tribonacci' );

tribonacci( n )

Computes the nth Tribonacci number.

var v = tribonacci( 0 );
// returns 0

v = tribonacci( 1 );
// returns 0

v = tribonacci( 2 );
// returns 1

v = tribonacci( 3 );
// returns 1

v = tribonacci( 63 );
// returns 8607945812375585

If n > 63, the function returns NaN, as larger Tribonacci numbers cannot be safely represented in double-precision floating-point format.

var v = tribonacci( 64 );
// returns NaN

If not provided a nonnegative integer value, the function returns NaN.

var v = tribonacci( 3.14 );
// returns NaN

v = tribonacci( -1 );
// returns NaN

If provided NaN, the function returns NaN.

var v = tribonacci( NaN );
// returns NaN

Examples

var tribonacci = require( '@stdlib/math-base-special-tribonacci' );

var v;
var i;

for ( i = 0; i < 64; i++ ) {
    v = tribonacci( i );
    console.log( v );
}

C APIs

Usage

#include "stdlib/math/base/special/tribonacci.h"

stdlib_base_tribonacci( n )

Computes the nth Tribonacci number.

double out = stdlib_base_tribonacci( 0 );
// returns 0

out = stdlib_base_tribonacci( 1 );
// returns 0

The function accepts the following arguments:

• n: [in] int32_t input value.

double stdlib_base_tribonacci( const int32_t n );

Examples

#include "stdlib/math/base/special/tribonacci.h"
#include <stdio.h>
#include <stdint.h>

int main( void ) {
    int32_t i;
    double v;

    for ( i = 0; i < 64; i++ ) {
        v = stdlib_base_tribonacci( i );
        printf( "tribonacci(%d) = %lf\n", i, v );
    }
}

See Also

• @stdlib/math-base/special/fibonacci: compute the nth Fibonacci number.

Notice

This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.

Community

License

See LICENSE.

Copyright

Copyright © 2016-2024. The Stdlib Authors.