%I A007457 M0224
%S A007457 0,1,2,2,2,2,4,4,2,2,4,4,6,4,4,6,8,6,6,6,4,8,8,8,8,8,8,6,10,8,10,10,8,
%T A007457 12,8,10,14,12,10,12,16,10,18,14,12,14,16,14,16,14,10,16,20,14,12,16,
%U A007457 14,20,18,14,22,20,16,20
%N A007457 # of (j,k): j+k=n, (j,n)=(k,n)=1, j,k square-free.
%D A007457 Problem 6623, Amer. Math. Monthly, 99 (1992), 573-575.
%D A007457 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, 
               Academic Press, 1995 (includes this sequence).
%Y A007457 Sequence in context: A060632 A151565 A160407 this_sequence A119802 A060369 
               A143979
%Y A007457 Adjacent sequences: A007454 A007455 A007456 this_sequence A007458 A007459 
               A007460
%K A007457 nonn,nice,easy
%O A007457 1,3
%A A007457 N. J. A. Sloane (njas(AT)research.att.com), Robert G. Wilson v (rgwv(AT)rgwv.com)