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A125097
a(n) is k such that k*(2n+1) mod 1000 = 123, or 2n+1 if no such k exists.
1
123, 41, 5, 589, 347, 193, 471, 15, 419, 217, 863, 701, 25, 449, 487, 133, 731, 35, 679, 157, 3, 561, 45, 109, 227, 473, 191, 55, 739, 697, 543, 621, 65, 569, 567, 213, 851, 75, 599, 837, 483, 881, 85, 829, 507, 353, 711, 95, 259, 577, 823, 341, 105, 889, 47, 893
OFFSET
0,1
COMMENTS
Contains odd numbers from 1 to 999. See patterns in graph.
EXAMPLE
n=3: a(3)=589 because 2n+1=7, 7*589 = 4123 = 123 (mod 1000).
n=499: a(499)=877 because 2n+1=999 and 999*877=876123 = 123 (mod 1000).
CROSSREFS
Sequence in context: A062233 A351406 A123171 * A302211 A308004 A192231
KEYWORD
nonn
AUTHOR
Zak Seidov, Nov 20 2006
STATUS
approved