diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7eaa5d0a7..5f65ca212 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3115,6 +3115,28 @@ This release closes the following issue:
+
+
+#### [@stdlib/math/base/special/factorialln](https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/math/base/special/factorialln)
+
+
+
+
+
+##### Features
+
+- [`1c43f05`](https://github.com/stdlib-js/stdlib/commit/1c43f05a04d6731ea7d1b93f89179da216259005) - add C implementation for `math/base/special/factorialln` [(#2731)](https://github.com/stdlib-js/stdlib/pull/2731 )
+
+
+
+
+
+
+
+
+
+
+
#### [@stdlib/math/base/special/fast/abs](https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/math/base/special/fast/abs)
@@ -5775,6 +5797,7 @@ A total of 30 people contributed to this release. Thank you to the following con
+- [`1c43f05`](https://github.com/stdlib-js/stdlib/commit/1c43f05a04d6731ea7d1b93f89179da216259005) - **feat:** add C implementation for `math/base/special/factorialln` [(#2731)](https://github.com/stdlib-js/stdlib/pull/2731 ) _(by Gunj Joshi)_
- [`b633157`](https://github.com/stdlib-js/stdlib/commit/b6331572f8cc0dcd92ac1dbeb0aeaabc4d858615) - **docs:** remove comments, set `isNegative` to `uint8_t` in `math/base/special/gammaln` [(#2732)](https://github.com/stdlib-js/stdlib/pull/2732) _(by Gunj Joshi)_
- [`759e667`](https://github.com/stdlib-js/stdlib/commit/759e6676d54a121a5458edbe0f6caa541c465001) - **feat:** add C implementation for `math/base/special/sinc` _(by Gunj Joshi)_
- [`06b8011`](https://github.com/stdlib-js/stdlib/commit/06b80119890e1868578ba4904e9efaa071b27b05) - **feat:** add C implementation for `math/base/special/binomcoef` _(by Gunj Joshi)_
diff --git a/base/special/factorialln/README.md b/base/special/factorialln/README.md
index 9c6d2ba52..b592aa2e8 100644
--- a/base/special/factorialln/README.md
+++ b/base/special/factorialln/README.md
@@ -166,6 +166,94 @@ for ( i = 0; i < x.length; i++ ) {
+
+
+* * *
+
+
+
+## C APIs
+
+
+
+
+
+
+
+
+
+
+
+### Usage
+
+```c
+#include "stdlib/math/base/special/factorialln.h"
+```
+
+#### stdlib_base_factorialln( x )
+
+Evaluates the natural logarithm of the [factorial function][factorial-function]. For input values other than negative integers, the function returns `ln( x! ) = ln( Γ(x+1) )`, where `Γ` is the [Gamma][gamma-function] function. For negative integers, the function returns `NaN`.
+
+```c
+double out = stdlib_base_factorialln( 3.0 );
+// returns ~1.792
+
+out = stdlib_base_factorialln( -1.5 );
+// returns ~1.266
+```
+
+The function accepts the following arguments:
+
+- **x**: `[in] double` input value.
+
+```c
+double stdlib_base_factorialln( const double n );
+```
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+### Examples
+
+```c
+#include "stdlib/math/base/special/factorialln.h"
+#include
+
+int main( void ) {
+ const double x[] = { 2.0, 3.0, 5.0, 8.0 };
+
+ double y;
+ int i;
+ for ( i = 0; i < 4; i++ ) {
+ y = stdlib_base_factorialln( x[ i ] );
+ printf( "factorialln(%lf) = %lf\n", x[ i ], y );
+ }
+}
+```
+
+
+
+
+
+
+
+
+