OFFSET
1,1
LINKS
Colin Barker, Table of n, a(n) for n = 1..1000
Index entries for linear recurrences with constant coefficients, signature (5,-5,1).
FORMULA
a(n) = 5*a(n-1)-5*a(n-2)+a(n-3) for n>3.
G.f.: 2*x*(x-3) / ((x-1)*(x^2-4*x+1)).
EXAMPLE
6 is in the sequence because (6+4)^3 - 6^3 = 28^2.
MATHEMATICA
LinearRecurrence[{5, -5, 1}, {6, 28, 110}, 30] (* Paolo Xausa, Mar 04 2024 *)
PROG
(PARI) Vec(2*x*(x-3)/((x-1)*(x^2-4*x+1)) + O(x^40))
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Colin Barker, Oct 30 2015
STATUS
approved