feat: add math/iter/sequences/tribonacci

PR-URL: #1393
Closes: #1331

Reviewed-by: Philipp Burckhardt <pburckhardt@outlook.com>

lib/node_modules/@stdlib/math/iter/sequences/tribonacci/README.md

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+<!--
+
+@license Apache-2.0
+
+Copyright (c) 2024 The Stdlib Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+-->
+
+# iterTribonacciSeq
+
+> Create an iterator which generates a [tribonacci sequence][tribonacci-number].
+
+<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->
+
+<section class="intro">
+
+The [Tribonacci numbers][tribonacci-number] are the integer sequence
+
+<!-- <equation class="equation" label="eq:tribonacci_sequence" align="center" raw="0, 0, 1, 1, 2, 4, 7, 13, 24, 44, 81, 149, 274, 504, 927, 1705, \ldots" alt="Tribonacci sequence"> -->
+
+```math
+0, 0, 1, 1, 2, 4, 7, 13, 24, 44, 81, 149, 274, \ldots
+```
+
+<!-- <div class="equation" align="center" data-raw-text="0, 0, 1, 1, 2, 4, 7, 13, 24, 44, 81, 149, 274, 504, 927, 1705, \ldots" data-equation="eq:tribonacci_sequence">
+    <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@3249a68fb57cd71148f87ef3b2774be70a04d80a/lib/node_modules/@stdlib/math/base/special/tribonacci/docs/img/equation_tribonacci_sequence.svg" alt="Tribonacci sequence">
+    <br>
+</div> -->
+
+<!-- </equation> -->
+
+The sequence is defined by the recurrence relation
+
+<!-- <equation class="equation" label="eq:tribonacci_recurrence_relation" align="center" raw="F_n = F_{n-1} + F_{n-2} + F_{n-3}" alt="Tribonacci sequence recurrence relation"> -->
+
+```math
+F_n = F_{n-1} + F_{n-2} + F_{n-3}
+```
+
+<!-- <div class="equation" align="center" data-raw-text="F_n = F_{n-1} + F_{n-2} + F_{n-3}" data-equation="eq:tribonacci_recurrence_relation">
+    <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@3249a68fb57cd71148f87ef3b2774be70a04d80a/lib/node_modules/@stdlib/math/base/special/tribonacci/docs/img/equation_tribonacci_recurrence_relation.svg" alt="Tribonacci sequence recurrence relation">
+    <br>
+</div> -->
+
+<!-- </equation> -->
+
+with seed values `F_0 = 0`, `F_1 = 0`, and `F_2 = 1`.
+
+</section>
+
+<!-- /.intro -->
+
+<!-- Package usage documentation. -->
+
+<section class="usage">
+
+## Usage
+
+```javascript
+var iterTribonacciSeq = require( '@stdlib/math/iter/sequences/tribonacci' );
+```
+
+#### iterTribonacciSeq( \[options] )
+
+Returns an iterator which generates a [Tribonacci sequence][tribonacci-number].
+
+```javascript
+var it = iterTribonacciSeq();
+// returns <Object>
+
+var v = it.next().value;
+// returns 0
+
+v = it.next().value;
+// returns 0
+
+v = it.next().value;
+// returns 1
+
+// ...
+```
+
+The returned iterator protocol-compliant object has the following properties:
+
+-   **next**: function which returns an iterator protocol-compliant object containing the next iterated value (if one exists) assigned to a `value` property and a `done` property having a `boolean` value indicating whether the iterator is finished.
+-   **return**: function which closes an iterator and returns a single (optional) argument in an iterator protocol-compliant object.
+
+The function supports the following `options`:
+
+-   **iter**: number of iterations. Default: `64`.
+
+The returned iterator can only generate the first `64` [Tribonacci numbers][tribonacci-number], as larger [Tribonacci numbers][tribonacci-number] cannot be safely represented in [double-precision floating-point format][ieee754]. By default, the function returns an iterator which generates all `64` numbers. To limit the number of iterations, set the `iter` option.
+
+```javascript
+var opts = {
+    'iter': 3
+};
+var it = iterTribonacciSeq( opts );
+// returns <Object>
+
+var v = it.next().value;
+// returns 0
+
+v = it.next().value;
+// returns 0
+
+v = it.next().value;
+// returns 1
+
+var bool = it.next().done;
+// returns true
+```
+
+</section>
+
+<!-- /.usage -->
+
+<!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+<section class="notes">
+
+## Notes
+
+-   If an environment supports `Symbol.iterator`, the returned iterator is iterable.
+
+</section>
+
+<!-- /.notes -->
+
+<!-- Package usage examples. -->
+
+<section class="examples">
+
+## Examples
+
+<!-- eslint no-undef: "error" -->
+
+```javascript
+var iterTribonacciSeq = require( '@stdlib/math/iter/sequences/tribonacci' );
+
+// Create an iterator:
+var it = iterTribonacciSeq();
+
+// Perform manual iteration...
+var v;
+while ( true ) {
+    v = it.next();
+    if ( v.done ) {
+        break;
+    }
+    console.log( v.value );
+}
+```
+
+</section>
+
+<!-- /.examples -->
+
+<!-- Section to include cited references. If references are included, add a horizontal rule *before* the section. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+<section class="references">
+
+</section>
+
+<!-- /.references -->
+
+<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->
+
+<section class="related">
+
+* * *
+
+## See Also
+
+-   <span class="package-name">[`@stdlib/math/base/special/tribonacci`][@stdlib/math/base/special/tribonacci]</span><span class="delimiter">: </span><span class="description">compute the nth Tribonacci number.</span>
+-   <span class="package-name">[`@stdlib/math/base/special/fibonacci`][@stdlib/math/base/special/fibonacci]</span><span class="delimiter">: </span><span class="description">compute the nth Fibonacci number.</span>
+-   <span class="package-name">[`@stdlib/math/iter/sequences/lucas`][@stdlib/math/iter/sequences/lucas]</span><span class="delimiter">: </span><span class="description">create an iterator which generates a Lucas sequence.</span>
+
+</section>
+
+<!-- /.related -->
+
+<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+<section class="links">
+
+[tribonacci-number]: https://en.wikipedia.org/wiki/Generalizations_of_Fibonacci_numbers#Tribonacci_numbers
+
+[ieee754]: https://en.wikipedia.org/wiki/IEEE_754-1985
+
+<!-- <related-links> -->
+
+[@stdlib/math/base/special/tribonacci]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/math/base/special/tribonacci
+
+[@stdlib/math/iter/sequences/lucas]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/math/iter/sequences/lucas
+
+[@stdlib/math/base/special/fibonacci]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/math/base/special/fibonacci
+
+<!-- </related-links> -->
+
+</section>
+
+<!-- /.links -->

lib/node_modules/@stdlib/math/iter/sequences/tribonacci/benchmark/benchmark.js

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+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2024 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var bench = require( '@stdlib/bench' );
+var isnan = require( '@stdlib/math/base/assert/is-nan' );
+var isIteratorLike = require( '@stdlib/assert/is-iterator-like' );
+var pkg = require( './../package.json' ).name;
+var iterTribonacciSeq = require( './../lib' );
+
+
+// MAIN //
+
+bench( pkg, function benchmark( b ) {
+	var iter;
+	var i;
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		iter = iterTribonacciSeq();
+		if ( typeof iter !== 'object' ) {
+			b.fail( 'should return an object' );
+		}
+	}
+	b.toc();
+	if ( !isIteratorLike( iter ) ) {
+		b.fail( 'should return an iterator protocol-compliant object' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});
+
+bench( pkg+'::iteration', function benchmark( b ) {
+	var iter;
+	var z;
+	var i;
+
+	iter = iterTribonacciSeq();
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		z = iter.next().value;
+		if ( isnan( z ) ) {
+			b.fail( 'should not be NaN' );
+		}
+	}
+	b.toc();
+	if ( isnan( z ) ) {
+		b.fail( 'should not be NaN' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});