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a(n) = n^5-n+1.
0

%I #25 Feb 17 2018 20:20:14

%S 1,1,31,241,1021,3121,7771,16801,32761,59041,99991,161041,248821,

%T 371281,537811,759361,1048561,1419841,1889551,2476081,3199981,4084081,

%U 5153611,6436321,7962601,9765601,11881351,14348881,17210341,20511121,24299971,28629121,33554401,39135361,45435391

%N a(n) = n^5-n+1.

%C This is the simplest polynomial whose roots cannot be expressed in terms of radicals.

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Quintic_function#Finding_roots_of_a_quintic_equation">Finding roots of a quintic equation</a>

%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (6,-15,20,-15,6,-1).

%F G.f.: ( 1-5*x+40*x^2+50*x^3+35*x^4-x^5 ) / (x-1)^6. - R. J. Mathar, Apr 26 2016

%t Table[n^5 - n + 1, {n, 0, 34}] (* _Michael De Vlieger_, Apr 26 2016 *)

%Y Cf. A271209

%K nonn,easy

%O 0,3

%A _Benjamin Przybocki_, Apr 23 2016