OFFSET
1,1
COMMENTS
For primes in this sequence see A146358.
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
EXAMPLE
a(1) = 421 because the continued fraction of (1 + sqrt(421))/2 = 10, 1, 3, 6, 1, 1, 2, 2, 1, 1, 6, 3, 1, 19, 1, 3, 6, ... has a period (1, 3, 6, 1, 1, 2, 2, 1, 1, 6, 3, 1, 19) of length 13.
MATHEMATICA
Select[Range[10^4], !IntegerQ @ Sqrt[#] && Length[ContinuedFraction[(1 + Sqrt[#])/2][[2]]] == 13 &]
CROSSREFS
KEYWORD
nonn
AUTHOR
Amiram Eldar, Mar 31 2020
STATUS
approved