A309474 Digits of one of the two 3-adic integers sqrt(-1/2).

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, 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, 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

Offset: 0

Author

Seiichi Manyama, Aug 04 2019

Keywords

• nonn
• base

Links

• Robert Israel, Table of n, a(n) for n = 0..10000

Crossrefs

Cf. A271223, A309475, A309476.

Programs

Maple

T:= select(t -> padic:-ratvaluep(t,1)=1, [padic:-rootp(x^2+1/2,3,100)]):
op([1,1,3],T); # Robert Israel, Aug 05 2019

PARI

Vecrev(digits(truncate(sqrt(-1/2+O(3^100))), 3))

Formula

p = ...122121, p^2 = ...111111.

q = A271223 = ...200211, p * q = ...000001.

a(n) = (b(n+1) - b(n))/3^n, with b(n) = A309476(n).