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A248500 Numbers m that are not coprime to A059995(m): floor(m/10).

%I A248500 #24 Nov 07 2014 03:47:26
%S A248500 2,3,4,5,6,7,8,9,20,22,24,26,28,30,33,36,39,40,42,44,46,48,50,55,60,
%T A248500 62,63,64,66,68,69,70,77,80,82,84,86,88,90,93,96,99,100,102,104,105,
%U A248500 106,108,110,120,122,123,124,126,128,129,130,140,142,144,146,147
%N A248500 Numbers m that are not coprime to A059995(m): floor(m/10).
%C A248500 Definition of 'being coprime' and special-case conventions are as in Wikipedia. In particular, when m<10 then floor(m/10)=0, and zero is coprime only to 1. The complementary sequence is A248499.
%H A248500 Stanislav Sykora, <a href="/A248500/b248500.txt">Table of n, a(n) for n = 1..20000</a>
%H A248500 Wikipedia, <a href="http://en.wikipedia.org/wiki/Coprime_integers">Coprime integers</a>
%F A248500 gcd(a(n),floor(a(n)/10)) > 1.
%e A248500 2 is a member because gcd(2,0)=2 > 1.
%e A248500 100 is also a member because gcd(100,10)=10 > 1.
%e A248500 125 is not a member because 125 and 12 are coprime, i.e., gcd(125,12)=1.
%o A248500 (PARI) a=vector(20000);
%o A248500 i=n=0; while(i++, if(gcd(i, i\10)!=1, a[n++]=i; if(n==#a, break))); a
%Y A248500 Cf. A059995, A248499, A248501, A248502.
%K A248500 nonn,base,easy
%O A248500 1,1
%A A248500 _Stanislav Sykora_, Oct 07 2014