Lower-Trimmed Subsequence
The lower-trimmed subsequence of 
is the sequence 
obtained by subtracting 1 from each 
andthen removing all 0s. If 
is a Fractal Sequence, then is a Fractal Sequence.If is a Signature Sequence, then 
.
References
Kimberling, C. ``Fractal Sequences and Interspersions.'' Ars Combin. 45, 157-168, 1997.
- Duality Principle
- Duality Theorem
- Dual Map
- Dual Polyhedron
- Dual Scalar
- Dual Solid
- Dual Tensor
- Dual Voting
- Du Bois Raymond Constants
- Duffing Differential Equation
- Duhamel's Convolution Principle
- Dumbbell Curve
- Duodecillion
- Dupin's Cyclide
- Dupin's Indicatrix
- Dupin's Theorem
- Duplication Formula
- Duplication of the Cube
- Durand's Rule
- Durfee Polynomial
- Durfee Square
- Dvoretzky's Theorem
- Dyad
- Dyadic
- Dyck's Theorem