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A156082 Maximum coefficient of the polynomial (-1)^(n+1)*Product_{k=1..n} (1 - x^k)^2.

%I A156082 #15 Jan 06 2021 23:08:07
%S A156082 1,2,3,4,6,8,12,19,24,36,52,74,103,156,223,322,470,682,992,1448,2120,
%T A156082 3072,4494,6538,9584,14001,20400,29928,43774,64032,93968,137520,
%U A156082 201766,296236,433746,637812,936334,1373622,2021344,2968872,4364300,6422472
%N A156082 Maximum coefficient of the polynomial (-1)^(n+1)*Product_{k=1..n} (1 - x^k)^2.
%H A156082 Robert Israel, <a href="/A156082/b156082.txt">Table of n, a(n) for n = 1..2405</a>
%H A156082 S. R. Finch, <a href="http://www.people.fas.harvard.edu/~sfinch/">Signum equations and extremal coefficients</a>.
%H A156082 Steven R. Finch, <a href="/A000980/a000980.pdf">Signum equations and extremal coefficients</a>, February 7, 2009. [Cached copy, with permission of the author]
%p A156082 P:= -1:
%p A156082 for n from 1 to 100 do
%p A156082   P:= expand(-P*(1-x^n)^2);
%p A156082   A[n]:= max(coeffs(P,x));
%p A156082 od:
%p A156082 seq(A[i],i=1..100); # _Robert Israel_, Mar 02 2018
%t A156082 Table[ -Min[CoefficientList[Expand[(-1)^n*Product[(1 - x^k)^2, {k, 1, n}]],x]], {n, 1, 50}]
%Y A156082 Cf. A133871.
%K A156082 nonn
%O A156082 1,2
%A A156082 _Steven Finch_, Feb 03 2009
%E A156082 Name edited by _Robert Israel_, Mar 02 2018