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%I #5 Dec 05 2013 19:55:45
%S 2,1,5,3,4,8,6,7,9,13,10,11,12,14,19,15,16,17,18,20,31,21,22,23,24,25,
%T 26,29,27,28,30,32,33,34,35,47,36,37,38,39,40,41,42,43,52,44,45,46,48,
%U 49,50,51,53,54,82,55,56,57,58,59,60,61,62,63,64,87,65,66,67,68,69,70
%N Group the positive integers so that the n-th group contains n numbers whose sum is a multiple of the n-th prime: (2), (1, 5), (3, 4, 8), (6, 7, 9, 13), (10, 11, 12, 14, 19), (15, 16, 17, 18, 20, 31), ...
%e 2; 1,5; 3,4,8; 6,7,9,13; 10,11,12,14,19; 15,16,17,18,20,31; ...
%Y Cf. A076058, A076059, A076060, A076061.
%K nonn,tabl
%O 1,1
%A _Amarnath Murthy_, Oct 05 2002
%E Corrected and extended by _Sascha Kurz_, Jan 20 2003