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A031598 Numbers n such that continued fraction for sqrt(n) has even period and central term 100. 1
10002, 10006, 10018, 10022, 10046, 10054, 10078, 10082, 10086, 10102, 10118, 10134, 10146, 10162, 10174, 10178, 10182, 10194, 10198, 10214, 10226, 10238, 10274, 10278, 10294, 10306, 10326, 10334, 10338, 10342, 10358, 10402, 22503, 22521, 22548, 22557 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..10000

PROG

(Python)

from __future__ import division

from sympy import continued_fraction_periodic

A031598_list = [n for n, s in ((i, continued_fraction_periodic(0, 1, i)[-1]) for i in range(1, 10**5)) if isinstance(s, list) and len(s) % 2 == 0 and s[len(s)//2-1] == 100] # Chai Wah Wu, Jun 10 2017

CROSSREFS

Sequence in context: A115850 A082567 A330135 * A210760 A164968 A165296

Adjacent sequences:  A031595 A031596 A031597 * A031599 A031600 A031601

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified April 6 10:18 EDT 2020. Contains 333273 sequences. (Running on oeis4.)