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A020430 Numbers n such that continued fraction for sqrt(n) has period 91. 1
4057, 8293, 10589, 11801, 11969, 12346, 12349, 12809, 17665, 17729, 19661, 19793, 20017, 20506, 21706, 21898, 23753, 26417, 28909, 29221, 29453, 31357, 32237, 32429, 32693, 34781, 40538, 41885, 41957, 43273, 43565, 45145, 46786, 47057, 49477, 52357 (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 sympy import continued_fraction_periodic

A020430_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) == 91] # Chai Wah Wu, Jun 08 2017

CROSSREFS

Sequence in context: A320207 A320216 A246801 * A163010 A069332 A118060

Adjacent sequences:  A020427 A020428 A020429 * A020431 A020432 A020433

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified June 13 06:38 EDT 2021. Contains 344981 sequences. (Running on oeis4.)