OFFSET
1,2
COMMENTS
Also nonnegative integers y in the solutions to 8*x^2-4*y^2+4*x+2*y+2 = 0, the corresponding values of x being A251601.
LINKS
Colin Barker, Table of n, a(n) for n = 1..654
Index entries for linear recurrences with constant coefficients, signature (35,-35,1).
FORMULA
a(n) = 35*a(n-1) - 35*a(n-2) + a(n-3).
G.f.: -x*(7*x^2-16*x+1) / ((x-1)*(x^2-34*x+1)).
a(n) = (2+(27-19*sqrt(2))*(17+12*sqrt(2))^n+(17+12*sqrt(2))^(-n)*(27+19*sqrt(2)))/8. - Colin Barker, Mar 02 2016
EXAMPLE
19 is in the sequence because H(19) = 703 = 325 + 378 = H(13) + H(14).
PROG
(PARI) Vec(-x*(7*x^2-16*x+1)/((x-1)*(x^2-34*x+1)) + O(x^20))
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Colin Barker, Dec 05 2014
STATUS
approved