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 6 modulo 17.
A322560 is the approximation (congruent to 11 mod 17) of another square root of 2 over the 17-adic field.
LINKS
Wikipedia, p-adic number
FORMULA
EXAMPLE
6^2 = 36 = 2*17 + 2;
244^2 = 59536 = 206*17^2 + 2;
4290^2 = 18404100 = 3746*17^3 + 2.
PROG
(PARI) a(n) = truncate(sqrt(2+O(17^n)))
CROSSREFS
KEYWORD
nonn
AUTHOR
Jianing Song, Aug 29 2019
STATUS
approved