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%I #9 Dec 06 2024 20:44:25
%S 6,9,10,8,15,9,10,21,16,27,28,15,33,35,9,39,16,28,44,45,32,50,51,52,
%T 27,28,57,15,63,44,69,35,16,75,52,32,81,28,87,44,45,93,64,98,99,50,68,
%U 52,105,27,110,111,32,76,117,16,123,63,129,130,44,135,136,92,35,141,32,147,75,152,153,154,52,159,64,81,165
%N Greatest non-abundant divisor of the n-th abundant number.
%H Antti Karttunen, <a href="/A378735/b378735.txt">Table of n, a(n) for n = 1..20000</a>
%F a(n) = A378665(A005101(n)).
%F a(n) >= A378736(n).
%o (PARI)
%o A294935(n) = (sigma(n)<=(2*n));
%o A378665(n) = { fordiv(n,d,if(A294935(n/d), return(n/d))); (1); };
%o k=0; n=0; while(k<105, n++; if(!A294935(n), k++; print1(A378665(n),", ")));
%Y Cf. A005101, A294935, A378665.
%Y Cf. also A378736 and the points of differences A378737.
%K nonn,new
%O 1,1
%A _Antti Karttunen_, Dec 06 2024