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Triangle read by rows: coefficients of auxiliary Rudin-Shapiro polynomials A_{ns}(omega) written in descending powers of x.
4

%I #31 Dec 21 2021 21:11:40

%S 2,1,1,-2,1,-3,1,-4,2,1,-5,5,1,-6,9,-2,1,-7,14,-7,1,-8,20,-16,2,1,-9,

%T 27,-30,9,1,-10,35,-50,25,-2,1,-11,44,-77,55,-11,1,-12,54,-112,105,

%U -36,2,1,-13,65,-156,182,-91,13,1,-14,77,-210,294,-196,49,-2,1,-15,90,-275,450,-378,140,-15

%N Triangle read by rows: coefficients of auxiliary Rudin-Shapiro polynomials A_{ns}(omega) written in descending powers of x.

%H Michael De Vlieger, <a href="/A213234/b213234.txt">Table of n, a(n) for n = 0..10200</a> (rows 0 <= n <= 200, flattened)

%H John Brillhart, John, J. S. Lomont, and Patrick Morton, <a href="http://gdz.sub.uni-goettingen.de/dms/resolveppn/?PPN=GDZPPN002192802">Cyclotomic properties of the Rudin-Shapiro polynomials</a>, J. Reine Angew. Math. 288 (1976), 37-65; see Table 2; MR0498479 (58 #16589).

%H Matty van Son, <a href="https://arxiv.org/abs/2108.02441">Equations of the Cayley Surface</a>, arXiv:2108.02441 [math.NT], 2021.

%F T(n,k) = (-1)^k*A034807(n,k). - _Philippe Deléham_ , Nov 10 2013

%e The first few polynomials are:

%e 2

%e x

%e x^2-2

%e x^3-3*x

%e x^4+2-4*x^2

%e x^5-5*x^3+5*x

%e x^6-2-6*x^4+9*x^2

%e x^7-7*x^5+14*x^3-7*x

%e x^8+2-8*x^6+20*x^4-16*x^2

%e x^9-9*x^7+27*x^5-30*x^3+9*x

%e x^10-2-10*x^8+35*x^6-50*x^4+25*x^2

%e x^11-11*x^9+44*x^7-77*x^5+55*x^3-11*x

%e x^12+2-12*x^10+54*x^8-112*x^6+105*x^4-36*x^2

%e ...

%e Triangle begins:

%e [2]

%e [1]

%e [1, -2]

%e [1, -3]

%e [1, -4, 2]

%e [1, -5, 5]

%e [1, -6, 9, -2]

%e [1, -7, 14, -7]

%e [1, -8, 20, -16, 2]

%e [1, -9, 27, -30, 9]

%e [1, -10, 35, -50, 25, -2]

%e [1, -11, 44, -77, 55, -11]

%e [1, -12, 54, -112, 105, -36, 2]

%e ...

%p #The program is valid for n>=1:

%p f:=n->x^n+add((-1)^i*(n/i)*binomial(n-i-1,i-1)*x^(n-2*i), i=1..floor(n/2));

%p g:=n->series(x^n*subs(x=1/x,f(n)),x,n+1);

%p h:=n->seriestolist(series(subs(x=sqrt(x),g(n)),x,n+1));

%p for n from 0 to 15 do lprint(h(n)); od:

%t Block[{t}, t[0, 0] = 2; t[n_, k_] := Binomial[n - k, k] + Binomial[n - k - 1, k - 1]; Table[(-1)^k*t[n, k], {n, 0, 15}, {k, 0, Floor[n/2]}] ] // Flatten (* _Michael De Vlieger_, Jun 26 2020, after _Jean-François Alcover_ at A034807 *)

%Y Cf. A034807, A132460.

%K sign,tabf

%O 0,1

%A _N. J. A. Sloane_, Jun 06 2012