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Digits of the 2-adic integer 7^(1/5).
4

%I #7 Sep 11 2019 20:38:38

%S 1,1,1,0,0,1,1,1,0,1,1,0,0,0,1,0,0,0,0,1,1,1,1,1,1,1,1,1,0,1,0,0,0,1,

%T 1,1,0,1,1,1,0,1,1,0,1,1,0,1,1,0,1,1,1,0,0,0,1,0,0,1,0,0,1,1,0,1,1,1,

%U 0,1,0,0,1,1,0,0,1,1,1,1,0,1,0,1,0,0,0,0

%N Digits of the 2-adic integer 7^(1/5).

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/P-adic_number">p-adic number</a>

%F a(n) = (A325894(n+1) - A325894(n))/2^n.

%F a(n) = 0 if A325894(n)^5 - 7 is divisible by 2^(n+1), otherwise a(n) = 1.

%e Equals ...1110111000101111111110000100011011100111.

%o (PARI) a(n) = lift(sqrtn(7+O(2^(n+1)), 5))\2^n

%Y Cf. A325894.

%Y Digits of p-adic fifth-power roots:

%Y A325896 (2-adic, 3^(1/5));

%Y A325897 (2-adic, 5^(1/5));

%Y this sequence (2-adic, 7^(1/5));

%Y A325899 (2-adic, 9^(1/5));

%Y A322169 (5-adic, 7^(1/5));

%Y A309445 (7-adic, 2^(1/5));

%Y A309446 (7-adic, 3^(1/5));

%Y A309447 (7-adic, 4^(1/5));

%Y A309448 (7-adic, 5^(1/5));

%Y A309449 (7-adic, 6^(1/5)).

%K nonn,base

%O 0

%A _Jianing Song_, Sep 07 2019