OFFSET
1,3
COMMENTS
Sequence extended to n = 1 using formula.
LINKS
Eric Weisstein's World of Mathematics, Moebius Ladder
Eric Weisstein's World of Mathematics, Vertex Cut
Index entries for linear recurrences with constant coefficients, signature (10,-35,48,-11,-22,7,4).
FORMULA
a(n) = 2^(2*n) - A286185(n) - 1. - Pontus von Brömssen, Aug 30 2022
a(n) = 4^n + n - LucasL(n, 2) - 3*n*Fibonacci(n, 2).
a(n) = 10*a(n-1) - 35*a(n-2) + 48*a(n-3) - 11*a(n-4) - 22*a(n-5) + 7*a(n-6) + 4*a(n-7).
G.f.: 2*x^3*(-4-x+14*x^2-5*x^3+2*x^4)/((-1+x)^2*(-1+4*x)*(-1+2*x+x^2)^2).
MATHEMATICA
Table[4^n + n - LucasL[n, 2] - 3 n Fibonacci[n, 2], {n, 20}]
LinearRecurrence[{10, -35, 48, -11, -22, 7, 4}, {0, 0, 8, 82, 512, 2644, 12364}, 20]
CoefficientList[Series[2 x^2 (-4 - x + 14 x^2 - 5 x^3 + 2 x^4)/((-1 + x)^2 (-1 + 4 x) (-1 + 2 x + x^2)^2), {x, 0, 20}], x]
CROSSREFS
KEYWORD
nonn
AUTHOR
Eric W. Weisstein, Aug 30 2022
EXTENSIONS
More terms from Pontus von Brömssen, Aug 30 2022
STATUS
approved