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A256566 a(n) is the central term of the (2n-1)-st row of triangle A256440.

%I A256566 #8 Apr 02 2015 11:24:56
%S A256566 1,3,3,3,9,9,9,2,2,2,21,21,21,21,21,21,21,21,21,21,21,21,38,46,46,46,
%T A256566 46,46,46,58,58,58,58,58,58,58,58,58,58,58,58,62,62,74,74,74,74,82,82,
%U A256566 74,74,74,62,74,74,74,74,74,62,74,74,82,82,82,82,82,82,82
%N A256566 a(n) is the central term of the (2n-1)-st row of triangle A256440.
%C A256566 All terms are deficient and after the 4th term sigma(n)/n appears to stay between 1.5 and 1.6.
%C A256566 Note that sequence is not monotonic and can return later to previous terms values.
%H A256566 Michel Marcus, <a href="/A256566/b256566.txt">Table of n, a(n) for n = 1..1000</a>
%o A256566 (PARI) lista(nn) = {forstep(n=1, nn, 2, v = vector(n, k, sigma(k)/k); w = vecsort(v,,1); print1(w[(n+1)/2], ", "););}
%Y A256566 Cf. A005100 (deficient numbers), A256440.
%K A256566 nonn
%O A256566 1,2
%A A256566 _Michel Marcus_, Apr 02 2015