Search: id:A073716
Results 1-1 of 1 results found.

%I A073716
%S A073716 1,3,9,20,30,40,44,80,84,100,114,168,174,192,208,244,256,272,300,316,
%T A073716 324,404,440,456,464,520,524,596,672,704,720,834,894,1044,1064,1248,
%U A073716 1272,1324,1416,1464,1604,1608,1626,1632,1636,1680,1686,1704,1744,1756
%N A073716 Numbers n such that the number of prime divisors of n (counted with multiplicity) 
               = number of anti-divisors of n.
%C A073716 See A066272 for definition of anti-divisor.
%e A073716 40 is a term since its prime factors are {2, 2, 2, 5} and its anti-divisors 
               are {3, 9, 16, 27}.
%o A073716 (PARI) {for(n=1,1800,v1=[]; v2=[]; v3=[]; ds=divisors(2*n-1); for(k=2,
               matsize(ds)[2]-1, if(ds[k]%2>0,v1=concat(v1,ds[k]))); ds=divisors(2*n); 
               for(k=2,matsize(ds)[2]-1,if(ds[k]%2>0, v2=concat(v2,ds[k]))); ds=divisors(2*n+1); 
               for(k=2,matsize(ds)[2]-1,if(ds[k]%2>0,v3=concat(v3,ds[k]))); v=vecsort(concat(v1,
               concat(v2,v3))); if(matsize(v)[2]==bigomega(n),print1(n,",")))}
%Y A073716 Cf. A001222, A066272.
%Y A073716 Sequence in context: A146066 A164283 A033315 this_sequence A037048 A139142 
               A037257
%Y A073716 Adjacent sequences: A073713 A073714 A073715 this_sequence A073717 A073718 
               A073719
%K A073716 nonn
%O A073716 1,2
%A A073716 Jason Earls (zevi_35711(AT)yahoo.com), Aug 30 2002
%E A073716 Edited and extended by Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), 
               Sep 02 2002

Search completed in 0.001 seconds