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Partition of positive numbers into shortest possible groups (1), (2,3), (4,5,6), (7,8), ... such that a(n) = the sum of the terms of the n-th group is a multiple of a(n-1).
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%I #2 Mar 30 2012 17:27:02

%S 1,5,15,15,30,210,1050,6300,1045800,13756453200,67826316310678800,

%T 8622353329220210792550912000,

%U 92206830102396929163916671718833533307592704000

%N Partition of positive numbers into shortest possible groups (1), (2,3), (4,5,6), (7,8), ... such that a(n) = the sum of the terms of the n-th group is a multiple of a(n-1).

%F a(n) = A000217(A160277(n)) - A000217(A160277(n-1))

%Y Cf. A160276 (ratios a(n)/a(n-1)), A160277 (last terms in the groups), A075631, A079798.

%K nonn

%O 1,2

%A _Max Alekseyev_, May 08 2009