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%I #17 Mar 30 2022 06:34:36
%S 2187,4782969,170859375,1801088541,10460353203,42618442977,
%T 137231006679,373669453125,897410677851,1954897493193,3938980639167,
%U 7446353252589,13348388671875,22876792454961,37725479487783,60170087060757,93206534790699,140710042265625,207616015289871
%N a(n) = (6*n + 3)^7.
%H Vincenzo Librandi, <a href="/A016951/b016951.txt">Table of n, a(n) for n = 0..2000</a>
%H <a href="/index/Rec#order_08">Index entries for linear recurrences with constant coefficients</a>, signature (8,-28,56,-70,56,-28,8,-1).
%F From _Amiram Eldar_, Mar 30 2022: (Start)
%F a(n) = A016945(n)^7.
%F a(n) = 3^7*A016759(n).
%F Sum_{n>=0} 1/a(n) = 127*zeta(7)/279936.
%F Sum_{n>=0} (-1)^n/a(n) = 61*Pi^7/403107840. (End)
%t a[n_] := (6*n + 3)^7; Array[a, 50, 0] (* _Amiram Eldar_, Mar 30 2022 *)
%o (Magma) [(6*n+3)^7: n in [0..40]]; // _Vincenzo Librandi_, May 05 2011
%Y Cf. A016759, A016945, A016946, A016947, A016948, A016949, A016950.
%Y Subsequence of A001015.
%K nonn,easy
%O 0,1
%A _N. J. A. Sloane_