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A357772
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Numbers with a sum of digits which is not 7-smooth.
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1
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29, 38, 47, 49, 56, 58, 65, 67, 74, 76, 83, 85, 89, 92, 94, 98, 119, 128, 137, 139, 146, 148, 155, 157, 164, 166, 173, 175, 179, 182, 184, 188, 191, 193, 197, 199, 209, 218, 227, 229, 236, 238, 245, 247, 254, 256, 263
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OFFSET
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1,1
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LINKS
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FORMULA
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a(n) ~ n.
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EXAMPLE
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2 + 9 = 11 which is not of the form 2^a*3^b*5^c*7^d, so 29 is in the sequence.
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PROG
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(PARI) smooth(n, s)=forprime(p=2, s, n/=p^valuation(n, p)); n==1
is(n)=!smooth(sumdigits(n), 7)
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CROSSREFS
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KEYWORD
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nonn,easy,base
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AUTHOR
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STATUS
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approved
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