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%I #7 Dec 20 2019 05:31:11
%S 4,9,604,1849,7123,29588,71056,317238,945414,1347895,3567705,4624025,
%T 8518502,1523051853,4353560959,7537630621,24916885136,41483524658,
%U 513849020166,1021228997529,1137756574012,1185967711155,1581191501535,1705826324526
%N Composite numbers n that divide the sum of all composite numbers <= n.
%F a(n) = A002808(A330579(n)).
%o (PARI) s=0; k=0; forcomposite (c=4, oo, k++; s+=c; if (s%c==0, print1 (c", ")))
%Y Cf. A002808, A007506 (prime variant), A330579.
%K nonn,more
%O 1,1
%A _Rémy Sigrist_, Dec 18 2019
%E a(15)-a(24) from _Giovanni Resta_, Dec 20 2019