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A369879 Number of different coefficient values in expansion of Product_{k=1..n} (1-x^k).

%I A369879 #14 Feb 04 2024 13:14:36
%S A369879 1,2,2,3,4,3,4,5,5,5,5,5,6,7,7,9,9,11,12,15,16,17,21,23,25,33,35,41,
%T A369879 43,53,55,77,74,97,85,135,111,175,131,223,157,269,187,315,219,375,245,
%U A369879 437,280,505,320,593,357,671,398,761,445,825,489,933,529,1039,576,1119,627,1211,682,1309,730,1415
%N A369879 Number of different coefficient values in expansion of Product_{k=1..n} (1-x^k).
%o A369879 (PARI) a(n) = #Set(Vec(prod(k=1, n, 1-x^k)));
%o A369879 (Python)
%o A369879 from collections import Counter
%o A369879 def A369879(n):
%o A369879     c = {0:1}
%o A369879     for k in range(1,n+1):
%o A369879         d = Counter(c)
%o A369879         for j in c:
%o A369879             d[j+k] -= c[j]
%o A369879         c = d
%o A369879     return len(set(c.values()))+int(max(c)+1>len(c)) # _Chai Wah Wu_, Feb 04 2024
%Y A369879 Cf. A010815, A039822, A369790.
%K A369879 nonn
%O A369879 0,2
%A A369879 _Seiichi Manyama_, Feb 04 2024