[Feature] Add Bell Number Calculator

[satyam-lgtm]

Description

The Bell Numbers count the possible partitions of a set. Bell Number calculator calculates the nth Bell number given whole number n.

Screenshots

No response

Checklist

• I have checked the existing issues.
• I follow Contributing Guidelines of this project.
• I am a KWOC'24 contributor.

Code of Conduct

• I agree to follow this project's "Code of Conduct".

[github-actions]

Hey @satyam-lgtm, Welcome to the project CalcDiverse! 🎊
Thanks for opening an issue! 🙌 Please wait for the issue to be assigned. Happy Coding!! ✨

[Rakesh9100]

Please give more description of this calculator, including what will be the inputs and result @satyam-lgtm

[satyam-lgtm]

Please give more description of this calculator, including what will be the inputs and result @satyam-lgtm

Example inputs and results:

Input: n = 3
Result: B_n = 5
As there are 5 ways to partition set of 3 elements:-
{1,2,3}
{1,2},{3}
{1,3},{2}
{2,3},{1}
{1},{2},{3}

[Rakesh9100]

Okay, go ahead @satyam-lgtm

[aprajitapandeyxcghd]

Would love to contribute to this. Can you assign me this? @Rakesh9100 SWOC'25