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%I #24 Nov 07 2014 03:47:46
%S 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,
%T 57,60,63,64,66,68,70,72,74,76,78,80,85,90,95,96,98,99,100,102,104,
%U 105,106,108,110,111,112,119,126,128,130,132,134,136,138,140,142
%N Numbers m that are not coprime to floor(m/16).
%C 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.
%H Stanislav Sykora, <a href="/A248502/b248502.txt">Table of n, a(n) for n = 1..20000</a>
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Coprime_integers">Coprime integers</a>
%F gcd(a(n),floor(a(n)/16)) > 1.
%e 2 is a member because gcd(2,0)=2 > 1.
%e 21 is not a member because floor(21/16)=1 and 1 is coprime to any number.
%e 200 is a member because floor(200/16)=12 and gcd(200,12)=4 > 1.
%o (PARI) a=vector(20000);
%o i=n=0; while(i++, if(gcd(i, i\16)!=1, a[n++]=i; if(n==#a, break))); a
%Y Cf. A248499, A248500, A248501.
%K nonn,base,easy
%O 1,1
%A _Stanislav Sykora_, Oct 07 2014
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