OFFSET
1,1
COMMENTS
Calculated using Dario Alpern's quadratic Diophantine solver, see link.
LINKS
Robin Visser, Table of n, a(n) for n = 1..10000
Dario Alpern, Generic two integer variable equation solver.
Eric Weisstein's World of Mathematics, Pell Equation.
EXAMPLE
The first fundamental solutions [x(n), y(n)] are (the first entry gives D(n)=a(n)):
[2, [0, 1]], [3, [1, 1]], [6, [2, 1]], [11, [3, 1]], [18, [4, 1]], [19, [13, 3]], [22, [14, 3]], [27, [5, 1]], [38, [6, 1]], [43, [59, 9]], [51, [7, 1]], [54, [22, 3]], [59, [23, 3]], [66, [8, 1]], [67, [221, 27]], [83, [9, 1]], [86, [102, 11]], [102, [10, 1]], [107, [31, 3]], [114, [32, 3]], [118, [554, 51]], [123, [11, 1]], [131, [103, 9]], [134, [382, 33]], [139, [8807, 747]], [146, [12, 1]], [162, [140, 11]], [163, [8005, 627]], [166, [41242, 3201]], [171, [13, 1]], [178, [40, 3]], [179, [2047, 153]], [187, [41, 3]], [198, [14, 1]], ...
PROG
(Python)
from itertools import count, islice
from sympy.solvers.diophantine.diophantine import diop_DN
def A377598_gen(startvalue=1): # generator of terms >= startvalue
return filter(lambda d:len(diop_DN(d, -2)), count(max(startvalue, 1)))
CROSSREFS
KEYWORD
nonn
AUTHOR
Robin Visser, Nov 02 2024
STATUS
approved