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A298249
Expansion of Product_{k>=1} (1 - x^(k*(k+1)*(2*k+1)/6)).
1
1, -1, 0, 0, 0, -1, 1, 0, 0, 0, 0, 0, 0, 0, -1, 1, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 1, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, -1, 1, 0, 0, 0, 0, -1, 1, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, -1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 0, 0, -1, 0, 1, 0, 0, 0, 1, -1, 0, -1, 1, 0, 0, 0, 1
OFFSET
0
COMMENTS
The difference between the number of partitions of n into an even number of distinct square pyramidal numbers and the number of partitions of n into an odd number of distinct square pyramidal numbers.
FORMULA
G.f.: Product_{k>=1} (1 - x^A000330(k)).
MATHEMATICA
nmax = 104; CoefficientList[Series[Product[1 - x^(k (k + 1) (2 k + 1)/6), {k, 1, nmax}], {x, 0, nmax}], x]
CROSSREFS
KEYWORD
sign
AUTHOR
Ilya Gutkovskiy, Jan 15 2018
STATUS
approved