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 A006309 M3912 #25 Jul 08 2025 16:47:04 %S A006309 1,5,-21,33,-65,85,-133,161,261,-341,-481,533,-645,705,901,-12803, %T A006309 -1281,-1541,1633,-1825,-14615,-11537,2581,-3201,3333 %N A006309 Coefficients of period polynomials. %D A006309 D. H. and Emma Lehmer, Cyclotomy for nonsquarefree moduli, pp. 276-300 of Analytic Number Theory (Philadelphia 1980), Lect. Notes Math. 899 (1981). %D A006309 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %H A006309 David Naccache and Ofer Yifrach-Stav, <a href="https://arxiv.org/abs/2301.01624">Pattern Recognition Experiments on Mathematical Expressions</a>, arXiv:2301.01624 [math.NT], 2022. %H A006309 Ofer Yifrach-Stav, <a href="https://hal.science/tel-04513104">Fast and Private Pool Testing and Contributions to Experimental Mathematics</a>, Doctoral thesis, École normale supérieure (Paris, France), HAL Science [math.cs] 2024, Art. No. tel-04513104. See pp. 108, 109, 212. %F A006309 a(n) = [x^(p-3)] f(p,x) where p = A000040(n) and f(p,x) is defined in A006308. - _Sean A. Irvine_, Mar 07 2017 %K A006309 sign,more %O A006309 2,2 %A A006309 _N. J. A. Sloane_ %E A006309 More terms, signs added, and offset corrected by _Sean A. Irvine_, Mar 07 2017