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A369987 Maximum of the absolute value of the coefficients of (1 - x) * (1 - x^8) * (1 - x^27) * ... * (1 - x^(n^3)).

%I A369987 #13 Feb 07 2024 19:22:13
%S A369987 1,1,1,1,1,1,2,2,2,3,3,4,7,7,7,8,11,18,23,28,32,40,55,58,83,118,128,
%T A369987 171,210,327,439,555,843,1009,1580,2254,3224,4703,6999,4573,6860,7760,
%U A369987 12563,15626,24451,33788,48806,51522,84103,120853,171206,312262,306080,464713,657411,892342
%N A369987 Maximum of the absolute value of the coefficients of (1 - x) * (1 - x^8) * (1 - x^27) * ... * (1 - x^(n^3)).
%t A369987 Table[Max[Abs[CoefficientList[Product[(1 - x^(k^3)), {k, 1, n}], x]]], {n, 0, 43}]
%o A369987 (PARI) a(n) = vecmax(apply(abs, Vec(prod(i=1, n, (1-x^(i^3)))))); \\ _Michel Marcus_, Feb 07 2024
%o A369987 (Python)
%o A369987 from collections import Counter
%o A369987 def A369987(n):
%o A369987     c = {0:1}
%o A369987     for k in range(1,n+1):
%o A369987         m, b = k**3, Counter(c)
%o A369987         for j in c:
%o A369987             b[j+m] -= c[j]
%o A369987         c = b
%o A369987     return max(map(abs,c.values())) # _Chai Wah Wu_, Feb 07 2024
%Y A369987 Cf. A000578, A160089, A279484, A359319, A369764, A369986.
%K A369987 nonn
%O A369987 0,7
%A A369987 _Ilya Gutkovskiy_, Feb 07 2024
%E A369987 More terms from _Michel Marcus_, Feb 07 2024