OFFSET
0,2
COMMENTS
For n > 0, a(n) is the unique solution to x^2 == 2 (mod 17^n) in the range [0, 17^n - 1] and congruent to 10 modulo 17.
A322563 is the approximation (congruent to 7 mod 17) of another square root of -2 over the 17-adic field.
LINKS
Wikipedia, p-adic number
FORMULA
EXAMPLE
10^2 = 100 = 6*17 - 2;
265^2 = 70225 = 243*17^2 - 2;
1421^2 = 2019241 = 411*17^3 - 2.
PROG
(PARI) a(n) = truncate(-sqrt(-2+O(17^n)))
CROSSREFS
KEYWORD
nonn
AUTHOR
Jianing Song, Aug 29 2019
STATUS
approved