OFFSET
0,2
COMMENTS
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..10000
BCMATH Congruence Programs, Finding a p-adic square root of a quadratic residue (mod p), p an odd prime.
FORMULA
EXAMPLE
a(4) = 3 because 2*261*3 + 109 = 1675 == 0 (mod 5).
a(4) = - 109*(2*261)^3 (mod 5) = -(-1)*(2*1)^3 (mod 5) = 8 (mod 5) = 3.
A268922(5) = 2136 = 1*5^0 + 2*5^1 + 0*5^2 + 2*5^3 + 3*5^4.
PROG
(PARI) a(n) = truncate(sqrt(-4+O(5^(n+1))))\5^n; \\ Michel Marcus, Mar 04 2016
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Wolfdieter Lang, Mar 02 2016
STATUS
approved