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Numbers n such that number of perfect partitions of n-1 divides n.
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%I #8 Dec 30 2019 10:05:32

%S 1,2,3,4,5,6,7,8,11,13,15,16,17,19,21,23,29,31,32,33,37,39,40,41,43,

%T 47,48,51,53,57,59,61,64,67,69,71,73,78,79,83,87,89,93,97,101,103,107,

%U 109,111,113,123,127,128,129,130,131,132,137,139,141,149,151,157

%N Numbers n such that number of perfect partitions of n-1 divides n.

%H Amiram Eldar, <a href="/A167211/b167211.txt">Table of n, a(n) for n = 1..10000</a>

%F {n: A002033(n-1) | n}.

%t f[1] = 1; f[n_] := f[n] = DivisorSum[n, f[#] &, # < n &]; Select[Range[100], Divisible[#, f[#]] &] (* _Amiram Eldar_, Dec 30 2019 *)

%Y Cf. A002033, A007694, A033950.

%K nonn

%O 1,2

%A _Juri-Stepan Gerasimov_, Oct 30 2009

%E Definition corrected by _R. J. Mathar_, May 21 2010

%E More terms from _Amiram Eldar_, Dec 30 2019