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A321108
Digits of one of the three 13-adic integers 5^(1/3) that is related to A321105.
13
11, 11, 5, 11, 2, 0, 9, 0, 6, 11, 9, 6, 7, 9, 2, 9, 9, 2, 3, 3, 8, 2, 7, 11, 6, 7, 4, 7, 10, 5, 5, 4, 11, 6, 2, 5, 2, 7, 10, 9, 9, 2, 9, 5, 7, 7, 4, 5, 10, 4, 1, 6, 4, 1, 4, 0, 4, 10, 11, 4, 12, 12, 7, 2, 9, 6, 11, 8, 5, 6, 11, 2, 0, 6, 6, 12, 10, 8, 12, 11, 2
OFFSET
0,1
COMMENTS
For k not divisible by 5, k is a cube in 13-adic field if and only if k == 1, 5, 8, 12 (mod 13). If k is a cube in 13-adic field, then k has exactly three cubic roots.
LINKS
Wikipedia, p-adic number
FORMULA
a(n) = (A321105(n+1) - A321105(n))/13^n.
EXAMPLE
The unique number k in [1, 13^3] and congruent to 11 modulo 13 such that k^3 - 5 is divisible by 13^3 is k = 999 = (5BB)_13, so the first three terms are 11, 11 and 5.
PROG
(PARI) a(n) = lift(sqrtn(5+O(13^(n+1)), 3) * (-1-sqrt(-3+O(13^(n+1))))/2)\13^n
CROSSREFS
For 5-adic cubic roots, see A290566, A290563, A309443.
Sequence in context: A135684 A220295 A300289 * A126610 A087380 A152986
KEYWORD
nonn,base
AUTHOR
Jianing Song, Aug 27 2019
STATUS
approved