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A369517
a(n) = [x^(n^4)] Product_{k=1..n} (x^(k^4) + 1 + 1/x^(k^4)).
0
1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 3, 9, 20, 43, 85, 183, 394, 1010, 2254, 5589, 12383, 31226, 71153, 182382, 426055, 1105686, 2615167, 6906858, 16607500, 44276140, 107836782, 290059089, 715361182, 1937639649, 4829754357, 13160903826, 33112002835, 90800047879
OFFSET
0,10
MAPLE
b:= proc(n, i) option remember; (m-> `if`(n>m, 0, `if`(n=m, 1, b(n, i-1)+
b(abs(n-i^4), i-1)+b(n+i^4, i-1))))(i*(i+1)*(2*i+1)*(3*i^2+3*i-1)/30)
end:
a:= n-> b(n^4, n):
seq(a(n), n=0..33); # Alois P. Heinz, Jan 25 2024
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Jan 25 2024
EXTENSIONS
a(34)-a(37) from Alois P. Heinz, Jan 25 2024
STATUS
approved