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%I #16 Jul 01 2018 17:24:55
%S 17,87,277,647,1257,2167,3437,5127,7297,10007,13317,17287,21977,27447,
%T 33757,40967,49137,58327,68597,80007,92617,106487,121677,138247,
%U 156257,175767,196837,219527,243897,270007
%N Concatenation of n^3 and 7.
%H Harry J. Smith, <a href="/A061679/b061679.txt">Table of n, a(n) for n = 1..1000</a>
%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (4,-6,4,-1).
%F a(n) = 10*n^3 + 7.
%F G.f.: -x*(-17 - 19*x - 31*x^2 + 7*x^3) / (x-1)^4. - _R. J. Mathar_, Feb 27 2015
%e a(3) = 277 because we can say 10 * 3^3 + 7 = 10 * 27 + 7 = 270 + 7 = 277.
%t (10 Range[30]^3)+7 (* or *) LinearRecurrence[{4,-6,4,-1},{17,87,277,647},30] (* _Harvey P. Dale_, Oct 20 2016 *)
%o (PARI) { for (n=1, 1000, write("b061679.txt", n, " ", 10*n^3 + 7) ) } \\ _Harry J. Smith_, Jul 26 2009
%Y Cf. A000578, A061722.
%K base,easy,nonn
%O 1,1
%A _Terrel Trotter, Jr._, Jun 23 2001
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