%I #28 Mar 12 2023 11:19:17
%S 1,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,33,35,37,39,41,43,
%T 45,47,49,50,52,53,55,56,58,59,61,62,65,67,69,71,73,75,77,79,81,82,83,
%U 84,86,87,88,89,91,92,93,94,97,101,103,107,109,113,114,115
%N Numbers m that are 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 A248502.
%H Stanislav Sykora, <a href="/A248501/b248501.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 1 is a member because gcd(1,0)=1.
%e 2 is not, because gcd(2,0)=2.
%e 129 is a member because 129 and floor(129/16)=8.
%t Select[Range[120],CoprimeQ[#,Floor[#/16]]&] (* _Harvey P. Dale_, Mar 12 2023 *)
%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, A248502.
%K nonn,base,easy
%O 1,2
%A _Stanislav Sykora_, Oct 07 2014
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