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A061679
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Concatenation of n^3 and 7.
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2
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17, 87, 277, 647, 1257, 2167, 3437, 5127, 7297, 10007, 13317, 17287, 21977, 27447, 33757, 40967, 49137, 58327, 68597, 80007, 92617, 106487, 121677, 138247, 156257, 175767, 196837, 219527, 243897, 270007
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refs;
listen;
history;
text;
internal format)
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OFFSET
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1,1
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LINKS
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Harry J. Smith, Table of n, a(n) for n = 1..1000
Index entries for linear recurrences with constant coefficients, signature (4,-6,4,-1).
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FORMULA
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a(n) = 10*n^3 + 7.
G.f.: -x*(-17 - 19*x - 31*x^2 + 7*x^3) / (x-1)^4. - R. J. Mathar, Feb 27 2015
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EXAMPLE
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a(3) = 277 because we can say 10 * 3^3 + 7 = 10 * 27 + 7 = 270 + 7 = 277.
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MATHEMATICA
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(10 Range[30]^3)+7 (* or *) LinearRecurrence[{4, -6, 4, -1}, {17, 87, 277, 647}, 30] (* Harvey P. Dale, Oct 20 2016 *)
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PROG
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(PARI) { for (n=1, 1000, write("b061679.txt", n, " ", 10*n^3 + 7) ) } \\ Harry J. Smith, Jul 26 2009
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CROSSREFS
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Cf. A000578, A061722.
Sequence in context: A080770 A118863 A118533 * A271567 A231704 A033654
Adjacent sequences: A061676 A061677 A061678 * A061680 A061681 A061682
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KEYWORD
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base,easy,nonn
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AUTHOR
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Terrel Trotter, Jr., Jun 23 2001
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STATUS
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approved
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