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 A158982 #20 Jan 05 2025 19:51:39
%S A158982 1,-2,1,-4,2,1,-8,20,-16,2,1,-16,104,-352,660,-672,336,-64,2,1,-32,
%T A158982 464,-4032,23400,-95680,283360,-615296,980628,-1136960,940576,-537472,
%U A158982 201552,-45696,5440,-256,2,1,-64,1952,-37760,520144,-5430656,44662464
%N A158982 Coefficients of polynomials P(n,x):=-2+P(n-1,x)^2, where P(0,x)=x-2.
%C A158982 The 2^n zeros of P(n,x) are 2+2*cos[(2k-1)Pi/(2^(n+1))], k=1,2,...,2^n.
%C A158982 P(n,x) = 2*T(2^(n+1),(1/2)x^(1/2)), where T(k,t) is the k-th Chebyshev polynomial of the first kind.
%H A158982 Clark Kimberling, <a href="https://web.archive.org/web/2024*/https://www.fq.math.ca/Papers1/48-3/Kimberling.pdf">Polynomials defined by a second-order recurrence, interlacing zeros, and Gray codes</a>, The Fibonacci Quarterly 48 (2010) 209-218.
%F A158982 P(n+1,x+2) = P(n,x^2) for n>=0.
%e A158982 Row 1: 1 -2 (from x-2)
%e A158982 Row 2: 1 -4 2 (from x^2-4x+2)
%e A158982 Row 3: 1 -8 20 -16 2
%e A158982 Row 4: 1 -16 104 -352 660 -672 336 -64 2
%o A158982 (PARI) tabf(nn) = {p = x-2; print(Vec(p)); for (n=2, nn, p = -2 + p^2; print(Vec(p)););} \\ _Michel Marcus_, Mar 01 2016
%Y A158982 Cf. A084534, A158983, A158984, A158985, A158986.
%K A158982 sign,tabf
%O A158982 1,2
%A A158982 _Clark Kimberling_, Apr 02 2009