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A095250
a(n) = 11111111... (n times) = (10^n-1)/9 reduced mod n.
4
0, 1, 0, 3, 1, 3, 1, 7, 0, 1, 1, 3, 1, 11, 6, 7, 1, 9, 1, 11, 6, 11, 1, 15, 11, 11, 0, 19, 1, 21, 1, 7, 12, 11, 16, 27, 1, 11, 33, 31, 1, 21, 1, 11, 36, 11, 1, 39, 36, 11, 9, 19, 1, 27, 1, 39, 54, 11, 1, 51, 1, 11, 27, 7, 61, 33, 1, 23, 42, 61, 1, 63, 1, 11, 36, 47, 23, 39, 1, 71, 0, 11, 1, 63
OFFSET
1,4
COMMENTS
a(p) = 1 if p is a prime; a(3^k) = 0.
REFERENCES
Amarnath Murthy, "On the divisors of Smarandache Unary Sequence", Smarandache Notions Journal, 1-2-3, vol. 11, 2000.
LINKS
FORMULA
a(n) = A002275(n) mod n.
EXAMPLE
1111111 mod 7 = 1.
MATHEMATICA
Table[Mod[FromDigits[PadRight[{}, n, 1]], n], {n, 90}] (* Harvey P. Dale, Jun 19 2022 *)
PROG
(PARI) a(n) = (10^n - 1)/9 % n; \\ Michel Marcus, Jul 03 2019
CROSSREFS
Cf. A002275.
Sequence in context: A281113 A361519 A236757 * A135521 A344763 A176032
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Jun 17 2004
STATUS
approved