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A290276
Numbers that are the sum of distinct odd positive cubes.
4
1, 27, 28, 125, 126, 152, 153, 343, 344, 370, 371, 468, 469, 495, 496, 729, 730, 756, 757, 854, 855, 881, 882, 1072, 1073, 1099, 1100, 1197, 1198, 1224, 1225, 1331, 1332, 1358, 1359, 1456, 1457, 1483, 1484, 1674, 1675, 1701, 1702, 1799, 1800, 1826, 1827, 2060, 2061, 2087, 2088, 2185, 2186, 2197, 2198, 2212
OFFSET
1,2
COMMENTS
Complement of A292740.
EXAMPLE
881 is in the sequence because 881 = 27 + 125 + 729 = 3^3 + 5^3 + 9^3.
MAPLE
N:= 10000: # to get all terms <= N
M:= floor(N^(1/3)):
G:= mul(1+x^(j^3), j=1..M, 2):
S:= series(G, x, N+1):
select(t -> coeff(S, x, t)>0, [$1..N]); # Robert Israel, Jul 26 2017
MATHEMATICA
max = 2212; f[x_] := Product[1 + x^(2 k + 1)^3, {k, 0, 8}]; Exponent[#, x] & /@ List @@ Normal[Series[f[x], {x, 0, max}]] // Rest
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Jul 25 2017
STATUS
approved