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A255680
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a(n) = n*(n mod 3)*(n mod 5).
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1
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0, 1, 8, 0, 16, 0, 0, 14, 48, 0, 0, 22, 0, 39, 112, 0, 16, 68, 0, 76, 0, 0, 44, 138, 0, 0, 52, 0, 84, 232, 0, 31, 128, 0, 136, 0, 0, 74, 228, 0, 0, 82, 0, 129, 352, 0, 46, 188, 0, 196, 0, 0, 104, 318, 0, 0, 112, 0, 174, 472, 0, 61, 248, 0, 256, 0, 0, 134, 408, 0, 0, 142, 0, 219, 592, 0, 76, 308, 0, 316, 0, 0, 164, 498, 0, 0, 172, 0
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OFFSET
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0,3
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COMMENTS
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a(n) = 0 for n = 3k and 5k, k=0,1,2,...
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LINKS
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Colin Barker, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0,0, 0, 0, 0, 0, 0, -1).
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FORMULA
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Empirical g.f.: x*(8*x^28 + 6*x^27 + 8*x^25 + 42*x^22 + 16*x^21 + 44*x^18 + 52*x^16 + 14*x^15 + 112*x^13 + 39*x^12 + 22*x^10 + 48*x^7 + 14*x^6 + 16*x^3 + 8*x + 1) / ((x - 1)^2*(x^2 + x + 1)^2*(x^4 + x^3 + x^2 + x + 1)^2*(x^8 - x^7 + x^5 - x^4 + x^3 - x + 1)^2). - Colin Barker, Mar 02 2015
a(n) = n*A010872(n)*A010874(n). - Michel Marcus, Mar 03 2015
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MATHEMATICA
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Table[x*(Mod[x, 3]*Mod[x, 5], {x, 0, 100}]
LinearRecurrence[{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1}, {0, 1, 8, 0, 16, 0, 0, 14, 48, 0, 0, 22, 0, 39, 112, 0, 16, 68, 0, 76, 0, 0, 44, 138, 0, 0, 52, 0, 84, 232}, 100] (* Harvey P. Dale, Sep 06 2015 *)
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PROG
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(PARI) vector(101, n, (n-1)*((n-1)%3)*((n-1)%5))
(MAGMA) [n*(n mod 3)*(n mod 5): n in [0..80]]; // Vincenzo Librandi, Mar 03 2015
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CROSSREFS
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Cf. A255642.
Sequence in context: A189764 A297811 A325318 * A265115 A214205 A278147
Adjacent sequences: A255677 A255678 A255679 * A255681 A255682 A255683
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KEYWORD
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nonn,easy
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AUTHOR
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Zak Seidov, Mar 01 2015
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STATUS
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approved
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