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A130227

Smallest integer y satisfying the Pell equation x^2 - n*y^2 = -1 for the values of n given in A031396.

1, 1, 1, 1, 5, 1, 1, 13, 1, 5, 1, 25, 13, 3805, 1, 125, 5, 1, 41, 53, 569, 1, 389, 851525, 73, 1, 61, 5, 149, 1, 9305, 385645, 1, 85, 82596761, 5, 126985, 1, 221, 17, 1, 113, 1517, 4574225, 281, 1, 373, 5, 85, 535979945, 63445, 1, 145, 23725, 7170685, 25, 19805, 1, 55335641, 13

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OFFSET

1,5

LINKS

Ray Chandler, Table of n, a(n) for n = 1..10000

PROG

(Python)

from itertools import count, islice

from sympy.solvers.diophantine.diophantine import diop_DN

def A130227_gen(startvalue=1): # generator of terms >= startvalue

for n in count(max(startvalue, 1)):

if len(d:=[a[1] for a in diop_DN(n, -1)]):