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A264349
The x member of the positive proper fundamental solution (x = x1(n), y = y1(n)) of the first class for the Pell equation x^2 - D(n)*y^2 = +8 for odd D(n) = A263012(n).
6
5, 7, 9, 217, 69, 11, 199, 13, 56445, 15, 6121, 46557, 17, 9567711, 127, 73829571, 19, 101080863, 21, 35927573, 1582431, 379, 23, 729, 167, 32899, 689581594497, 25, 1348157, 207495429, 1255, 27, 146613, 278601383, 29, 21751, 4777049027, 33814353, 19022653, 5062449, 31, 43541, 225
OFFSET
1,1
COMMENTS
The corresponding y = y1(n) member is given by A264350(n).
See A263012 for details and examples.
FORMULA
a(n)^2 - D(n)*y1(n)^2 = 8 with D(n) = A263012(n) and y1(n) = A264350(n), n >= 1.
EXAMPLE
n=1: 5^2 - 17*1^2 = 8. n=4: 217^2 - 89*23^2 = 8.
CROSSREFS
KEYWORD
nonn
AUTHOR
Wolfdieter Lang, Nov 17 2015
STATUS
approved