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A359320
Maximal coefficient of (1 + x) * (1 + x^16) * (1 + x^81) * ... * (1 + x^(n^4)).
4
1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 3, 3, 4, 5, 5, 6, 9, 13, 17, 24, 34, 53, 84, 130, 177, 290, 500, 797, 1300, 2066, 3591, 6090, 10298, 17330, 29888, 50811, 88358, 153369, 280208, 481289, 845090, 1474535, 2703811, 4808816, 8329214, 14806743, 27529781, 48859783, 87674040, 156471632
OFFSET
0,10
LINKS
MAPLE
f:= proc(n) local i; max(coeffs(expand(mul(1+x^(i^4), i=1..n)))) end proc:
map(f, [$1..50]); # Robert Israel, Dec 26 2022
PROG
(PARI) a(n) = vecmax(Vec(prod(k=1, n, 1+x^(k^4)))); \\ Michel Marcus, Dec 26 2022
(Python)
from collections import Counter
def A359320(n):
c = {0:1, 1:1}
for i in range(2, n+1):
j, d = i**4, Counter(c)
for k in c:
d[k+j] += c[k]
c = d
return max(c.values()) # Chai Wah Wu, Jan 31 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Dec 25 2022
EXTENSIONS
a(38)-a(50) from Seiichi Manyama, Dec 26 2022
STATUS
approved