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A078131
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Numbers which can be written as sum of cubes > 1.
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4
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8, 16, 24, 27, 32, 35, 40, 43, 48, 51, 54, 56, 59, 62, 64, 67, 70, 72, 75, 78, 80, 81, 83, 86, 88, 89, 91, 94, 96, 97, 99, 102, 104, 105, 107, 108, 110, 112, 113, 115, 116, 118, 120, 121, 123, 124, 125, 126, 128, 129, 131, 132, 133, 134, 135, 136, 137, 139, 140
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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EXAMPLE
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35 is in the sequence because 35 = 27 + 8.
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MAPLE
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a:=proc(n) local h, hser: h:=1/product(1-x^(j^3), j=2..30): hser:=series(h, x=0, 150): if coeff(hser, x^n)>0 then n else fi end: seq(a(n), n=1..140); # Emeric Deutsch, Mar 30 2006
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MATHEMATICA
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terms = 60;
(Exponent[#, x]& /@ List @@ Normal[1/Product[1-x^j^3, {j, 2, Ceiling[(3 terms)^(1/3)]}] + O[x]^(3 terms)])[[2 ;; terms+1]] (* Jean-François Alcover, Aug 04 2018, after Emeric Deutsch *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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