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Group the natural numbers so that the n-th group contains n numbers one each of a multiple of numbers from 1 to n so that the group sum is a multiple of (n+1): (2), (1, 8), (3, 4, 9), (5, 6, 12, 32), (7, 10, 15, 16, 30), (11, 14, 18, 20, 25, 24), ... Sequence gives initial terms of groups.
5

%I #7 Sep 24 2018 16:53:14

%S 2,1,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,

%T 89,97,101,103,107,109,113,127,131,137,139,149,151,157,163,167,173,

%U 179,181,191,193,197,199,211,223,227,229,233,239,241,251,257,263,269,271,277

%N Group the natural numbers so that the n-th group contains n numbers one each of a multiple of numbers from 1 to n so that the group sum is a multiple of (n+1): (2), (1, 8), (3, 4, 9), (5, 6, 12, 32), (7, 10, 15, 16, 30), (11, 14, 18, 20, 25, 24), ... Sequence gives initial terms of groups.

%C Is this the same sequence as A076074? - _Andrew S. Plewe_, Apr 30 2007

%Y Cf. A075644, A075645, A075646, A075647 (gives the list of groups).

%K nonn

%O 1,1

%A _Amarnath Murthy_, Sep 30 2002

%E More terms from _David Wasserman_, Jan 22 2005