Pentagonal number calculator
Pentagonal numbers grow from nested pentagon patterns. Paste or type n to see P(n)—often paired with partition function examples in number theory.
ClientNearby workflows on Toolcore
- Triangular number calculator — Compute the nth triangular number (1, 3, 6, 10, …) from a non‑negative integer—local arithmetic only. when units or numeric output should be checked on a related calculator.
- Hexagonal number calculator — Find H(n)=n(2n−1), the nth hexagonal figurate number—client-side integer math. when units or numeric output should be checked on a related calculator.
- Math expression evaluator — Evaluate basic + − × ÷ arithmetic with parentheses in your browser—no variables. when units or numeric output should be checked on a related calculator.
- Prime factorization — Factor whole numbers into prime products—BigInt trial division in your browser, no upload. when units or numeric output should be checked on a related calculator.
Common use cases
- Check figurate-number tables for recreational math writeups.
- Generate OEIS-style samples without leaving the browser.
Common mistakes to avoid
Confusing with triangular
Pentagonal uses 3n−1 in the numerator, not n+1.
FAQ
What is P(1)?
P(1)=1.
More tools
Related utilities you can open in another tab—mostly client-side.
Triangular number calculator
ClientCompute the nth triangular number (1, 3, 6, 10, …) from a non‑negative integer—local arithmetic only.
Hexagonal number calculator
ClientFind H(n)=n(2n−1), the nth hexagonal figurate number—client-side integer math.
Math expression evaluator
ClientEvaluate basic + − × ÷ arithmetic with parentheses in your browser—no variables.
Prime factorization
ClientFactor whole numbers into prime products—BigInt trial division in your browser, no upload.