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%I #21 Apr 01 2022 09:10:47
%S 625,14641,83521,279841,707281,1500625,2825761,4879681,7890481,
%T 12117361,17850625,25411681,35153041,47458321,62742241,81450625,
%U 104060401,131079601,163047361,200533921,244140625,294499921,352275361,418161601,492884401,577200625,671898241
%N a(n) = (6*n + 5)^4.
%H Vincenzo Librandi, <a href="/A016972/b016972.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (5,-10,10,-5,1).
%F From _Chai Wah Wu_, Mar 20 2017: (Start)
%F a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n > 4.
%F G.f.: (-x^4 - 2396*x^3 - 16566*x^2 - 11516*x - 625)/(x - 1)^5. (End)
%F From _Amiram Eldar_, Apr 01 2022: (Start)
%F a(n) = A016969(n)^4 = A016970(n)^2.
%F Sum_{n>=0} 1/a(n) = PolyGamma(3, 5/6)/7776. (End)
%t Table[(6 n + 5)^4, {n, 0, 20}] (* _Michael De Vlieger_, Mar 20 2017 *)
%o (Magma) [(6*n+5)^4: n in [0..40]]; // _Vincenzo Librandi_, May 07 2011
%Y Cf. A016969, A016970, A016971.
%Y Subsequence of A000583.
%K nonn,easy
%O 0,1
%A _N. J. A. Sloane_
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