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A239220
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Cubes that are not divisible by any of their nonzero digits.
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4
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27, 343, 6859, 24389, 50653, 79507, 97336, 205379, 300763, 456533, 493039, 636056, 704969, 2048383, 2924207, 3307949, 3869893, 4330747, 4657463, 4826809, 5735339, 6539203, 7645373, 7880599, 23639903, 26730899, 28934443, 30664297, 33698267, 38272753, 42508549
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OFFSET
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1,1
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COMMENTS
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Sequence is infinite because it contains (2*10^k + 3)^3, for k>1 and k not of the form 6*h + 2. - Giovanni Resta, Mar 13 2014
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LINKS
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FORMULA
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EXAMPLE
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50653 is in the sequence because 37^3 = 50653 is not divisible by 3, 5 or 6.
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MATHEMATICA
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ndnzdQ[n_]:=NoneTrue[n/Select[IntegerDigits[n], #!=0&], IntegerQ]; Select[ Range[ 400]^3, ndnzdQ] (* Harvey P. Dale, Jan 16 2022 *)
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PROG
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(PARI) isOK(n) = my(v=vecsort(digits(n^3), , 8)); for(i=1+(v[1]==0), #v, if(n^3%v[i]==0, return(0))); 1
s=[]; for(n=1, 1000, if(isOK(n), s=concat(s, n^3))); s
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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