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A369764
Maximal coefficient of (1 - x) * (1 - x^8) * (1 - x^27) * ... * (1 - x^(n^3)).
2
1, 1, 1, 1, 1, 1, 2, 2, 2, 3, 3, 4, 7, 7, 7, 8, 11, 18, 23, 28, 32, 40, 55, 58, 81, 118, 128, 171, 204, 327, 395, 555, 843, 1009, 1580, 2254, 3224, 4703, 6999, 4573, 6255, 7760, 12563, 15626, 22328, 33788, 47750, 51522, 84103, 120853, 168565, 312262, 306080
OFFSET
0,7
MAPLE
b:= proc(n) b(n):= `if`(n=0, 1, expand(b(n-1)*(1-x^(n^3)))) end:
a:= n-> max(coeffs(b(n))):
seq(a(n), n=0..52); # Alois P. Heinz, Jan 31 2024
PROG
(PARI) a(n)=vecmax(Vec(prod(k=1, n, 1-x^(k^3))));
vector(30, n, a(n-1)) \\ Joerg Arndt, Jan 31 2024
(Python)
from collections import Counter
def A369764(n):
c = {0:1, 1:-1}
for i in range(2, n+1):
d = Counter(c)
for k in c:
d[k+i**3] -= c[k]
c = d
return max(c.values()) # Chai Wah Wu, Jan 31 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Jan 31 2024
EXTENSIONS
a(45)-a(52) from Alois P. Heinz, Jan 31 2024
STATUS
approved