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%I #10 Jun 16 2015 14:22:24
%S 2,3,124,10714158
%N a(n) is the least positive integer x with A054973(x) = n and A258913(x) < x.
%C Is a(n) well-defined for all n?
%C For n > 1, a(n) belongs to sequence A258931.
%C The terms a(k), for 4 <= k <= 100, if they exist, are larger than 3*10^10. - _Giovanni Resta_, Jun 15 2015
%e For n=2, sigma(x)=124 for x=48 and 75, and 48+75 = 123 < 124.
%e For n=3, sigma(x)=10714158 for x=3031200, 3417300, and 3987450; and their sum is 10435950 (<10714158).
%o (PARI) a(n)=x=0;while(x++,u=List();for(i=1,x,if(sigma(i)==x,listput(u,i)));if(#u==n&vecsum(Vec(u))<x,return(x))) \\ not optimized because the same sigma values are calculated over and over again instead of being kept
%Y Cf. A054973, A258913, A258931, A007368, A258914.
%K nonn,more
%O 0,1
%A _Jeppe Stig Nielsen_, Jun 15 2015