OFFSET
1,1
COMMENTS
Also nonnegative integers y in the solutions to 18*x^2-6*y^2+24*x+4*y+18 = 0, the corresponding values of x being A251624.
It seems that the least significant digit of each term is 3.
LINKS
Colin Barker, Table of n, a(n) for n = 1..291
Index entries for linear recurrences with constant coefficients, signature (2703,-2703,1).
FORMULA
a(n) = 2703*a(n-1)-2703*a(n-2)+a(n-3).
G.f.: -3*x*(x^2-462*x+161) / ((x-1)*(x^2-2702*x+1)).
a(n) = (1 + 2*(sqrt(3)+2)*(1351+780*sqrt(3))^(-n) - 2*(sqrt(3)-2)*(1351+780*sqrt(3))^n) / 3. - Colin Barker, May 30 2017
EXAMPLE
483 is in the sequence because N(483) = 698901 = 231296+232965+234640 = N(278)+N(279)+N(280).
PROG
(PARI) Vec(-3*x*(x^2-462*x+161)/((x-1)*(x^2-2702*x+1)) + O(x^100))
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Colin Barker, Dec 06 2014
STATUS
approved