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%I #6 May 24 2020 04:00:35
%S 1,4,12,16,20,54,35,64,72,130,77
%N Sum of terms in row n of A081521.
%o (PARI) a(n) = {my(m=n*(n-1)/2, v); forstep(k=m+n/(2-n%2), oo, n, v=List([]); for(i=2, k-m, if(gcd(n, i)==1, listput(v, i))); if(#v>n-2, forsubset([#v, n-1], w, if(r=1+sum(i=1, n-1, v[w[i]])==k, return(k))))); } \\ _Jinyuan Wang_, May 23 2020
%Y Cf. A081521, A081522, A081524.
%K nonn,more
%O 1,2
%A _Amarnath Murthy_, Mar 27 2003
%E a(8)-a(11) from _Jinyuan Wang_, May 23 2020
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