A369773 Maximal coefficient of (1 + x) * (1 + x - x^2) * ... * (1 + x - x^2 + ... - (-x)^n).
1, 1, 2, 3, 4, 6, 19, 59, 233, 1189, 7046, 45326, 356517, 3108808, 30028121, 325635647, 3830546752, 49403859787, 685063715374, 10162709827329, 162776892315940, 2754021620252692, 49463507801582609, 940216720983170113, 18786988751008626812
Offset: 0
Keywords
Programs
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Mathematica
Table[Max[CoefficientList[Product[(1 - Sum[(-x)^j, {j, 1, i}]), {i, 1, n}], x]], {n, 0, 24}] -
Python
from collections import Counter def A369773(n): c = {0:1} for k in range(1,n+1): d = Counter(c) for j in c: a = c[j] for i in range(1,k+1): d[j+i] += (a if i&1 else -a) c = d return max(c.values()) # Chai Wah Wu, Feb 01 2024