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A225441
10-adic integer x such that x^7 = -7/9.
2
3, 3, 6, 5, 9, 8, 0, 3, 1, 9, 2, 2, 9, 2, 4, 9, 3, 1, 3, 9, 4, 0, 7, 4, 3, 6, 7, 8, 6, 4, 6, 8, 1, 7, 7, 1, 3, 8, 8, 0, 1, 7, 8, 4, 6, 0, 3, 0, 1, 0, 0, 2, 8, 0, 2, 4, 3, 4, 8, 2, 9, 2, 3, 5, 5, 4, 1, 3, 5, 3, 1, 0, 7, 0, 1, 1, 6, 7, 9, 9, 8, 1, 7, 2, 0, 8, 4, 1, 3, 1, 7, 4, 3, 5, 3, 7, 0, 6, 4, 2
OFFSET
0,1
LINKS
EXAMPLE
3^7 == 7 (mod 10).
33^7 == 77 (mod 10^2).
633^7 == 777 (mod 10^3).
5633^7 == 7777 (mod 10^4).
95633^7 == 77777 (mod 10^5).
895633^7 == 777777 (mod 10^6).
PROG
(PARI) n=0; for(i=1, 100, m=7*(10^i-1)/9; for(x=0, 9, if(((n+(x*10^(i-1)))^7)%(10^i)==m, n=n+(x*10^(i-1)); print1(x", "); break)))
(PARI) N=100; Vecrev(digits(lift(chinese(Mod((-7/9+O(2^N))^(1/7), 2^N), Mod((-7/9+O(5^N))^(1/7), 5^N)))), N) \\ Seiichi Manyama, Aug 06 2019
CROSSREFS
Sequence in context: A280167 A257143 A080512 * A102245 A038167 A307967
KEYWORD
nonn,base
AUTHOR
Aswini Vaidyanathan, May 11 2013
STATUS
approved