Irrotational Field
A Vector Field 
for which the Curl vanishes,
See also Beltrami Field, Conservative Field, Solenoidal Field, Vector Field
- Pythagorean Square Puzzle
- Pythagorean Theorem
- Pythagorean Triad
- Pythagorean Triangle
- Pythagorean Triple
- Pépin's Test
- Pépin's Theorem
- Pólya-Burnside Lemma
- Pólya Conjecture
- Pólya Distribution
- Pólya Enumeration Theorem
- Pólya Polynomial
- Pólya's Random Walk Constants
- Pólya-Vinogradov Inequality
- Pósa's Theorem
- Q
- q-Analog
- q-Beta Function
- q-Binomial Coefficient
- q-Binomial Theorem
- q-Cosine
- q-Derivative
- q-Dimension
- Q.E.D
- q-Extension