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A307702
Clique covering number of the n-Sierpinski tetrahedron graph.
1
1, 4, 11, 41, 161, 641, 2561, 10241, 40961, 163841, 655361, 2621441, 10485761, 41943041, 167772161, 671088641, 2684354561, 10737418241, 42949672961, 171798691841, 687194767361, 2748779069441, 10995116277761, 43980465111041, 175921860444161, 703687441776641
OFFSET
1,2
LINKS
Eric Weisstein's World of Mathematics, Clique Covering Number
Eric Weisstein's World of Mathematics, Sierpinski Tetrahedron Graph
FORMULA
a(n) = A199209(n-2) = 10*4^(n-3) for n >= 3.
From Colin Barker, Jul 20 2019: (Start)
G.f.: x*(1 + 2*x)*(1 - 3*x + x^2) / ((1 - x)*(1 - 4*x)).
a(n) = 5*a(n-1) - 4*a(n-2) for n>4.
(End)
PROG
(PARI) Vec(x*(1 + 2*x)*(1 - 3*x + x^2) / ((1 - x)*(1 - 4*x)) + O(x^30)) \\ Colin Barker, Jul 20 2019
CROSSREFS
Cf. A199209.
Sequence in context: A149269 A149270 A306188 * A214167 A278988 A214188
KEYWORD
nonn,easy
AUTHOR
Eric W. Weisstein, Apr 22 2019
EXTENSIONS
More terms from Colin Barker, Jul 20 2019
STATUS
approved