OFFSET
1,1
COMMENTS
Subsequence of A017377.
LINKS
FORMULA
a(n) = 2*A081017(n) - 1.
a(n) = 10*A089508(n) + 9.
a(n) = 8*a(n-1) - 8*a(n-2) + a(n-3).
G.f.: x*(19 - 3*x - x^2)/((1 - x)*(1 - 7*x + x^2)). - Stefano Spezia, Jun 22 2022
EXAMPLE
2*(L(4)^2)^3 + 2*(-L(5)^2)^3 + (149)^3 = 2*(49)^3 + 2*(-121)^3 + (149)^3 = 125, a(2) = 149.
MATHEMATICA
LinearRecurrence[{7, -1}, {19, 149}, 21]-1 + LucasL[2*Range[21]-3]^2
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
XU Pingya, Jun 20 2022
STATUS
approved