%I A080195
%S A080195 11,22,33,44,55,66,77,88,99,110,121,132,154,165,176,198,220,231,242,264,
%T A080195 275,297,308,330,352,363,385,396,440,462,484,495,528,539,550,594,605,
%U A080195 616,660,693,704,726,770,792,825,847,880,891,924,968,990,1056,1078,1089
%N A080195 11-smooth numbers which are not 7-smooth.
%C A080195 Numbers of the form 2^r*3^s*5^t*7^u*11^v with r, s, t, u >= 0, v > 0.
%e A080195 33 = 3*11 is a term but 35 = 5*7 is not.
%o A080195 (PARI) {m=1100; z=[]; for(r=0,floor(log(m)/log(2)),a=2^r; for(s=0,floor(log(m/
a)/log(3)),b=a*3^s; for(t=0, floor(log(m/b)/log(5)),c=b*5^t; for(u=0,
floor(log(m/c)/log(7)),d=c*7^u; for(v=1,floor(log(m/d)/log(11)),
z=concat(z,d*11^v)))))); z=vecsort(z); for(i=1,length(z),print1(z[i],
","))}
%Y A080195 Cf. A051038, A002473.
%Y A080195 Sequence in context: A059632 A008593 A135499 this_sequence A004920 A136613
A113585
%Y A080195 Adjacent sequences: A080192 A080193 A080194 this_sequence A080196 A080197
A080198
%K A080195 easy,nonn
%O A080195 1,1
%A A080195 Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Feb 10 2003
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