Tridiagonal Matrix
A Matrix with Nonzero elements only on the diagonal and slots horizontally or vertically adjacent the diagonal. Ageneral 
tridiagonal Matrix has the form
Inversion of such a matrix requires only
(as opposed to 
) arithmetic operations (Acton 1990).See also Diagonal Matrix, Jacobi Algorithm
References
Acton, F. S. Numerical Methods That Work, 2nd printing. Washington, DC: Math. Assoc. Amer., p. 103, 1990. Press, W. H.; Flannery, B. P.; Teukolsky, S. A.; and Vetterling, W. T. ``Tridiagonal and Band Diagonal Systems of Equations.'' §2.4 in Numerical Recipes in FORTRAN: The Art of Scientific Computing, 2nd ed. Cambridge, England: Cambridge University Press, pp. 42-47, 1992.
- Kaprekar Routine
- Kaps-Rentrop Methods
- Kapteyn Series
- Karatsuba Multiplication
- k-ary Divisor
- Katona's Problem
- Kauffman Polynomial F
- Kauffman Polynomial X
- k-Chain
- k-Circuit
- k-Coloring
- Kei
- Keith Number
- Keller's Conjecture
- Kelvin Functions
- Kelvin's Conjecture
- Kelvin Transformation
- Kempe Linkage
- Kepler Conjecture
- Kepler-Poinsot Solid
- Kepler Problem
- Kepler's Equation
- Kepler's Folium
- Kepler Solid
- Ker