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 A095250 a(n) = 11111111... (n times) = (10^n-1)/9 reduced mod n. 3
 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 (list; graph; refs; listen; history; text; internal format)
 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. PROG (PARI) a(n) = (10^n - 1)/9 % n; \\ Michel Marcus, Jul 03 2019 CROSSREFS Cf. A002275. Sequence in context: A050336 A281113 A236757 * A135521 A344763 A176032 Adjacent sequences:  A095247 A095248 A095249 * A095251 A095252 A095253 KEYWORD nonn AUTHOR Amarnath Murthy, Jun 17 2004 STATUS approved

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Last modified December 1 10:49 EST 2021. Contains 349428 sequences. (Running on oeis4.)