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A306189
Number of minimum dominating sets in the n-Sierpinski sieve graph.
3
3, 6, 2, 392, 1656976026, 122836566640423857273582993856, 50043395758253154294953783566500246788902420299683914045600060272160541415159062540151890
OFFSET
1,1
LINKS
Eric Weisstein's World of Mathematics, Minimum Dominating Set
Eric Weisstein's World of Mathematics, Sierpinski Sieve Graph
PROG
(PARI) a(n)={my(s=[[1+O(x), 0, 0, 0], [0, 0, x+O(x^2)], [0, x^2+O(x^3)], [x^3+O(x^4)]]); for(k=2, n, s=vector(4, i, vector(5-i, j, sum(xy=0, 3, sum(xz=0, 3, sum(yz=0, 3, s[1+(i>1)+!xy+!xz][1+(j>3)+(xy%2)+(xz%2)]*s[1+(i>2)+!xy+!yz][1+(j>2)+(xy\2)+(yz%2)]*s[1+(i>3)+!xz+!yz][1+(j>1)+(xz\2)+(yz\2)]/x^(!xy+!xz+!yz))))))); pollead([1, 3, 3, 1]*vectorv(4, i, s[i][5-i]))} \\ Christian Sievers, Jul 21 2024, improved Jul 25 2024
CROSSREFS
Sequence in context: A372921 A367028 A349863 * A216803 A094118 A375691
KEYWORD
nonn
AUTHOR
Eric W. Weisstein, Jan 28 2019
EXTENSIONS
a(5) and beyond from Christian Sievers, Jul 21 2024
STATUS
approved