A347536 Number of minimum dominating sets in the complete tripartite graph K_{n,n,n}.
3, 15, 27, 48, 75, 108, 147, 192, 243, 300, 363, 432, 507, 588, 675, 768, 867, 972, 1083, 1200, 1323, 1452, 1587, 1728, 1875, 2028, 2187, 2352, 2523, 2700, 2883, 3072, 3267, 3468, 3675, 3888, 4107, 4332, 4563, 4800, 5043, 5292, 5547, 5808, 6075, 6348, 6627
Offset: 1
Links
- Eric Weisstein's World of Mathematics, Complete Tripartite Graph
- Eric Weisstein's World of Mathematics, Minimum Dominating Set
- Index entries for linear recurrences with constant coefficients, signature (3,-3,1).
Formula
a(n) = A033428(n) = 3*n^2 for n != 2.
G.f.: 3*x*(-1 - 2*x + 3*x^2 - 3*x^3 + x^4)/(-1 + x)^3.
From Stefano Spezia, Sep 06 2021: (Start)
E.g.f.: 3*x*(x + 2*exp(x)*(1 + x))/2.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n > 5. (End)