OFFSET
1,1
COMMENTS
The continued fraction expansion of sqrt((j*m)^2+t*m) for m >= 1 where t divides 2*j has the form [j*m, 2*j/t, 2*j*m, 2*j/t, 2*j*m, ...]. Thus numbers of the form (71*m)^2 + 2*m for m >= 1 are in the sequence. Are there any others? - Chai Wah Wu, Jun 18 2016
The term 25776072 is not of the form (71*m)^2 + 2*m. - Chai Wah Wu, Jun 19 2016
LINKS
Chai Wah Wu, Table of n, a(n) for n = 1..10000
MATHEMATICA
lt71Q[n_]:=Module[{s=Sqrt[n]}, If[IntegerQ[s], 0, Min[ContinuedFraction[s] [[2]]]] == 71]; Select[Range[43*10^5], lt71Q] (* Harvey P. Dale, Apr 11 2017 *)
PROG
(Python)
from sympy import continued_fraction_periodic
A031749_list = [n for n, d in ((n, continued_fraction_periodic(0, 1, n)[-1]) for n in range(1, 10**5)) if isinstance(d, list) and min(d) == 71] # Chai Wah Wu, Jun 09 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved