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A248502
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Numbers m that are not coprime to floor(m/16).
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6
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2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 32, 34, 36, 38, 40, 42, 44, 46, 48, 51, 54, 57, 60, 63, 64, 66, 68, 70, 72, 74, 76, 78, 80, 85, 90, 95, 96, 98, 99, 100, 102, 104, 105, 106, 108, 110, 111, 112, 119, 126, 128, 130, 132, 134, 136, 138, 140, 142
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OFFSET
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1,1
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COMMENTS
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Definition of 'being coprime' and special-case conventions are as in Wikipedia. In particular, when m<16 then floor(m/16)=0, and zero is coprime only to 1. The complementary sequence is A248501.
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LINKS
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FORMULA
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gcd(a(n),floor(a(n)/16)) > 1.
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EXAMPLE
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2 is a member because gcd(2,0)=2 > 1.
21 is not a member because floor(21/16)=1 and 1 is coprime to any number.
200 is a member because floor(200/16)=12 and gcd(200,12)=4 > 1.
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PROG
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(PARI) a=vector(20000);
i=n=0; while(i++, if(gcd(i, i\16)!=1, a[n++]=i; if(n==#a, break))); a
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CROSSREFS
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KEYWORD
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nonn,base,easy
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AUTHOR
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STATUS
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approved
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