A339938 - OEIS

%I #8 Dec 24 2020 04:47:45

%S 15015,19635,21945,23205,25935,26565,31395,33495,33915,35805,39585,

%T 41055,42315,42735,45885,47355,49665,50505,51765,54285,55965,58695,

%U 61215,64155,68145,70455,72345,75075,77385,80535,82005,83265,84315,91245,95865,102795,105105

%N Odd non-coreful abundant numbers: the odd terms of A308127.

%C First differs from A112643, A129485 and A249263 at n = 28.

%H Amiram Eldar, <a href="/A339938/b339938.txt">Table of n, a(n) for n = 1..10000</a>

%e 15015 is a term since it is odd and the sum of its non-coreful divisors is A308135(15015) = 17241 > 15015.

%t f[p_, e_] := (p^(e + 1) - 1)/(p - 1); fc[p_, e_] := f[p, e] - 1; s[1] = 0; s[n_] := Times @@ (f @@@ FactorInteger[n]) - Times @@ (fc @@@ FactorInteger[n]); Select[Range[1, 10^5, 2], s[#] > # &]

%Y Intersection of A005408 and A308127.

%Y Cf. A308135.

%Y Similar sequences: A005231, A094889, A112643, A127666, A129485, A249263, A293186, A321147, A333950.

%K nonn

%O 1,1

%A _Amiram Eldar_, Dec 23 2020