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%I #18 Aug 05 2019 15:30:48
%S 1,2,1,2,2,1,2,0,1,1,1,0,2,1,2,0,1,2,0,1,0,0,1,2,0,2,1,1,1,2,2,2,1,0,
%T 1,2,1,2,1,1,2,1,2,0,0,1,2,1,1,1,0,1,0,1,2,1,2,1,2,2,0,2,1,0,1,2,1,0,
%U 2,1,2,1,0,2,1,2,2,0,2,1,1,2,0,2,0,2,0,2,2,0,2,2,0,0,0,1,2
%N Digits of one of the two 3-adic integers sqrt(-1/2).
%H Robert Israel, <a href="/A309474/b309474.txt">Table of n, a(n) for n = 0..10000</a>
%F p = ...122121, p^2 = ...111111.
%F q = A271223 = ...200211, p * q = ...000001.
%F a(n) = (b(n+1) - b(n))/3^n, with b(n) = A309476(n).
%p T:= select(t -> padic:-ratvaluep(t,1)=1, [padic:-rootp(x^2+1/2,3,100)]):
%p op([1,1,3],T); # _Robert Israel_, Aug 05 2019
%o (PARI) Vecrev(digits(truncate(sqrt(-1/2+O(3^100))), 3))
%Y Cf. A271223, A309475, A309476.
%K nonn,base
%O 0,2
%A _Seiichi Manyama_, Aug 04 2019