%I A077462
%S A077462 0,1,2,2,3,2,4,2,5,3,4,2,6,2,4,4,7,2,8,2,6,4,4,2,9,3,4,5,6,2,10,2,11,4,
%T A077462 4,4,12,2,4,4,9,2,10,2,6,6,4,2,13,3,8,4,6,2,14,4,9,4,4,2,15,2,4,6,16,4,
%U A077462 10,2,6,4,10,2,17,2,4,8,6,4,10,2,13,7,4,2,15,4,4,4,9,2,18,4,6,4,4,4,19
%N A077462 Number of prime factor configuration patterns.
%C A077462 Call two numbers equivalent if they have the same prime factorization
exponent partition. This sequence enumerates the equivalence classes.
%C A077462 A055932(a(n)) = A071364(n). - David Wasserman (wasserma(AT)spawar.navy.mil),
Dec 21 2004
%H A077462 S. Whealton, <a href="http://www.washingtonart.net/whealton/pfcn.html">
Prime Factor Configuration Pattern Numbers</a>.
%o A077462 (PARI) a(n)=local(vn); if(n<1,return(0)); vn=factor(n)[,2]; for(i=1,n,
if(vn==factor(i)[,2],return(#Set(vector(i,j,factor(j)[,2])))))
%Y A077462 Sequence in context: A001616 A144371 A101296 this_sequence A129294 A117658
A067540
%Y A077462 Adjacent sequences: A077459 A077460 A077461 this_sequence A077463 A077464
A077465
%K A077462 nonn,easy
%O A077462 0,3
%A A077462 Michael Somos, Nov 07 2002
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