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A225205
Denominators of convergents to the square root of the golden ratio.
7
1, 3, 4, 11, 125, 386, 2055, 2441, 26465, 28906, 84277, 450291, 1435150, 7626041, 9061191, 25748423, 112054883, 137803306, 249858189, 637519684, 2799936925, 143434302859, 146234239784, 728371261995, 1602976763774, 3934324789543, 123567045239607
OFFSET
0,2
FORMULA
a(n) = A331692(n)*a(n-1) + a(n-2) for n >= 2. - Jianing Song, Aug 18 2022
EXAMPLE
1, 4/3, 5/4, 14/11, 159/125, 491/386, 2614/2055, 3105/2441, 33664/26465, ... = A225204/A225205
MATHEMATICA
Denominator[Convergents[Sqrt[GoldenRatio], 20]]
CROSSREFS
Cf. A001622, A139339, A331692, A225204 (numerators).
Sequence in context: A102013 A192223 A079940 * A343931 A041299 A001112
KEYWORD
nonn,frac
AUTHOR
Eric W. Weisstein, May 01 2013
STATUS
approved