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A117771
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Numbers n such that digit sum of 2^n is less than or equal to n.
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0
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OFFSET
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1,1
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COMMENTS
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Probably there are no more terms.
Probably 5 and 70 are the only cases when digit sum of 2^n is equal to n. - Tanya Khovanova, Jul 23 2006
Probably 1, 2, 5 and 70 are the only cases when digit sum of 2^n is divisible by n. - Zak Seidov, Jul 24 2006
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LINKS
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MATHEMATICA
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Select[Range[80], #>=Total[IntegerDigits[2^#]]&] (* Harvey P. Dale, Sep 22 2019 *)
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PROG
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(PARI) isok(n) = d = digits(2^n); sum(i=1, #d, d[i]) <= n; \\ Michel Marcus, Aug 17 2013
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CROSSREFS
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KEYWORD
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nonn,base,fini
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AUTHOR
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STATUS
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approved
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