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%I #4 Dec 05 2013 19:55:33
%S 4,6,8,12,14,18,20,24,25,36,48,52,69,104,112,129,160,187,207,243,259,
%T 291,301,310,315,333,356,361,388,425,450,471,519,528,608,633,665,668,
%U 687,721,783,790,875,897,994,1016,1047,1138,1174,1179,1274,1278,1344
%N Group successively larger composite numbers so that the sum of the n-th group is a multiple of n. Sequence gives the first term in each group.
%t NextComposite[n_] := Block[{k = n + 1}, While[PrimeQ[k], k++ ]; k]; a = {}; k = 1; Do[s = 0; a = Append[a, NextComposite[k]]; While[k = NextComposite[k]; s = s + k; ! IntegerQ[s/n], ], {n, 1, 55}]; a
%Y Cf. A002808, A074129, A074120, A074122, A074123.
%K nonn
%O 1,1
%A _Amarnath Murthy_, Aug 27 2002
%E Edited, corrected and extended by _Robert G. Wilson v_, Aug 29 2002