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A347501
Number of dominating sets in the n-alkane graph.
1
17, 81, 405, 2025, 10125, 50625, 253125, 1265625, 6328125, 31640625, 158203125, 791015625, 3955078125, 19775390625, 98876953125, 494384765625, 2471923828125, 12359619140625, 61798095703125, 308990478515625, 1544952392578125, 7724761962890625
OFFSET
1,1
LINKS
Eric Weisstein's World of Mathematics, Alkane Graph
Eric Weisstein's World of Mathematics, Dominating Set
FORMULA
a(n) = 81*5^(n-2) for n > 1.
G.f.: x*(4*x - 17)/(5*x - 1).
E.g.f.: (81*exp(5*x) + 20*x - 81)/25. - Stefano Spezia, Sep 04 2021
MATHEMATICA
Join[{17}, LinearRecurrence[{5}, {81}, 20]]
CoefficientList[Series[(4 x - 17)/(5 x - 1), {x, 0, 20}], x]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Eric W. Weisstein, Sep 04 2021
STATUS
approved