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A395554
Number of no-overhang stacked partitions (teeth) of base 5 and total size n.
1
1, 5, 9, 16, 28, 45, 68, 98, 137, 188, 251, 328, 421, 534, 667, 823, 1006, 1217, 1459, 1736, 2050, 2406, 2805, 3251, 3749, 4303, 4915, 5589, 6331, 7145, 8034, 9004, 10058, 11203, 12443, 13782, 15227, 16783, 18454, 20247, 22168, 24223, 26416, 28755, 31246, 33896
OFFSET
5,2
COMMENTS
A tooth of base r is a finite stack of rows of unit cubes with bottom row of length r, weakly decreasing row lengths, and no row overhanging the row beneath it. This sequence is column c=5 of the triangle A072704.
REFERENCES
Paul M. King, Generating Functions for Temperley's No-Overhang Stacked Partitions, Journal of Integer Sequences (submitted).
FORMULA
G.f.: h_5(q) = q^5*(1+q)*(1+4q+3q^2+2q^3+3q^4+q^5+q^6)/((1-q)*(1-q^2)*(1-q^3)*(1-q^4)*(1-q^5)).
T(5,N) = [q^N] h_5(q) where h_r(q) satisfies (1-q^r)*h_r(q) = 2q*h_{r-1}(q) - q^2*h_{r-2}(q), with h_0(q)=1 and h_1(q)=q/(1-q).
CROSSREFS
Column 5 of A072704.
Cf. A000012 (c=1), A001477 (c=2), A000212 (c=3, with offset), A395553 (c=4).
Sequence in context: A233184 A356675 A072174 * A188555 A020958 A020750
KEYWORD
nonn,easy,new
AUTHOR
Paul M. King, Apr 28 2026
STATUS
approved