This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A060887 #34 Dec 26 2024 14:31:19 %S A060887 1,13,8191,797161,22369621,305175781,2612138803,16148168401, %T A060887 78536544841,317733228541,1111111111111,3452271214393,9726655034461, %U A060887 25239592216021,61054982558011,139013933454241,300239975158033,619036127056621,1224880286215951,2336276859014281,4311578947368421 %N A060887 a(n) = Sum_{j=0..12} n^j. %C A060887 a(n) = Phi_13(n) where Let Phi_k is the k-th cyclotomic polynomial. %H A060887 Harry J. Smith, <a href="/A060887/b060887.txt">Table of n, a(n) for n = 0..1000</a> %H A060887 <a href="/index/Cy#CyclotomicPolynomialsValuesAtX">Index to values of cyclotomic polynomials of integer argument</a> %H A060887 <a href="/index/Rec#order_13">Index entries for linear recurrences with constant coefficients</a>, signature (13,-78,286,-715,1287,-1716,1716,-1287,715,-286,78,-13,1). %F A060887 a(n) = n^12 + n^11 + n^10 + n^9 + n^8 + n^7 + n^6 + n^5 + n^4 + n^3 + n^2 + n + 1. %F A060887 G.f.: (x^12 + 2718*x^11 + 363156*x^10 + 8452952*x^9 + 59276439*x^8 + 155812164*x^7 + 167537592*x^6 + 74214648*x^5 + 12642423*x^4 + 691406*x^3 + 8100*x^2 + 1)/(1-x)^13. - _Colin Barker_, Oct 29 2012 %F A060887 a(n) = (n^13-1)/(n-1) with a(1) = 13 = lim_{x->1} a(x). - _M. F. Hasler_, Dec 31 2012 %p A060887 A060887 := proc(n) %p A060887 numtheory[cyclotomic](13,n) ; %p A060887 end proc: %p A060887 seq(A060887(n),n=0..20) ; # _R. J. Mathar_, Feb 11 2014 %t A060887 Table[1 + Sum[n^j, {j, 1, 12}], {n, 0, 20}] (* _G. C. Greubel_, Apr 14 2019 *) %o A060887 (PARI) a(n) = { n^12 + n^11 + n^10 + n^9 + n^8 + n^7 + n^6 + n^5 + n^4 + n^3 + n^2 + n + 1 } \\ _Harry J. Smith_, Jul 14 2009 %o A060887 (PARI) A060887(n)=polcyclo(13,n) \\ _M. F. Hasler_, Dec 31 2012 %o A060887 (Magma) [(&+[n^j: j in [0..12]]): n in [0..20]]; // _G. C. Greubel_, Apr 14 2019 %o A060887 (Sage) [sum(n^j for j in (0..12)) for n in (0..20)] # _G. C. Greubel_, Apr 14 2019 %Y A060887 Cf. A053698, A053699, A053700, A053716, A053717, A102909, A103623, A060885, A102909, A104376, A104682, A105067. %K A060887 nonn,easy %O A060887 0,2 %A A060887 _N. J. A. Sloane_, May 05 2001 %E A060887 Name changed by _G. C. Greubel_, Apr 14 2019