%I #3 Mar 30 2012 17:27:42
%S 20,30,42,48,54,56,72,80,88,90,96,99,104,108,110,117,120,126,130,132,
%T 140,143,150,154,156,160,168,180,182,192,195,204,208,210,216,221,224,
%U 228,234,238,240,252,255,264,266,270,272,280,285,288,294,300,304,306
%N Numbers n such that A095163(n) is different from A033677(n).
%C A095163(n) <= A033677(n).
%e A095163(54) = 6, A033677(54) = 9, so 54 is in the sequence.
%e For n = 12 we have divisors 1, 2, 3, 4, 6, 12; 1 occurs earlier once, 2 occurs earlier twice, 3 occurs earlier 3 times, but 4 occurs earlier only once, hence a(12) = 4.
%o (PARI) {m=310;v=vector(m);for(n=1,m,d=divisors(n);j=1;while(v[d[j]]>=d[j],j++);x=d[j];v[d[j]]=v[d[j]]+1;r=sqrt(n);j=1;while(d[j]<r,j++);y=d[j];if(x!=y,print1(n,",")))}
%o (PARI) {m=80;v=vector(m);for(n=1,m,d=divisors(n);j=1;while(v[d[j]]>=d[j],j++);print1(d[j],",");v[d[j]]=v[d[j]]+1)}
%Y Cf. A095163, A033677.
%K nonn
%O 1,1
%A _Klaus Brockhaus_, Jun 05 2004
|