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A364668
Lower independence number of the n-Goldberg graph.
0
0, 3, 5, 7, 9, 11, 14, 16, 18, 20, 22, 25, 27, 29, 31, 33, 36, 38, 40, 42, 44, 47, 49, 51, 53, 55, 58, 60, 62, 64, 66, 69, 71, 73, 75, 77, 80, 82, 84, 86, 88, 91, 93, 95, 97, 99, 102, 104, 106, 108, 110, 113, 115, 117, 119, 121, 124, 126, 128, 130, 132
OFFSET
0,2
COMMENTS
Extended to n = 0 using the formula/recurrence.
Disagrees with A195167(n) at n = 26, 31, 36, 41, ....
LINKS
Eric Weisstein's World of Mathematics, Goldberg Graph
Eric Weisstein's World of Mathematics, Lower Independence Number
FORMULA
a(n) = a(n-1) + a(n-5) - a(n-6).
G.f.: x*(3+2*x+2*x^2+2*x^3+2*x^4)/((-1+x)^2*(1+x+x^2+x^3+x^4)).
MATHEMATICA
Table[(11 n - Cos[2 n Pi/5] - Cos[4 n Pi/5] + Sqrt[1 + 2/Sqrt[5]] Sin[2 n Pi/5] + Sqrt[1 - 2/Sqrt[5]] Sin[4 n Pi/5] + 2)/5, {n, 0, 20}]
LinearRecurrence[{1, 0, 0, 0, 1, -1}, {0, 3, 5, 7, 9, 11}, 20]
CoefficientList[Series[x (3 + 2 x + 2 x^2 + 2 x^3 + 2 x^4)/((-1 + x)^2 (1 + x + x^2 + x^3 + x^4)), {x, 0, 20}], x]
CROSSREFS
Sequence in context: A195179 A033038 A195167 * A211218 A291839 A134917
KEYWORD
nonn
AUTHOR
Eric W. Weisstein, Aug 01 2023
STATUS
approved