cp's OEIS Frontend

A337688 Numbers divisible by 2 or more primitive nondeficient numbers.

%I A337688 #25 Oct 24 2020 17:24:27
%S A337688 60,84,120,140,168,180,210,240,252,264,280,300,312,336,360,420,440,
%T A337688 480,504,520,528,540,560,588,600,616,624,630,660,672,700,720,728,756,
%U A337688 780,792,816,840,880,900,912,924,936,960,980,1008,1020,1040,1050,1056,1080,1092
%N A337688 Numbers divisible by 2 or more primitive nondeficient numbers.
%C A337688 A006039 lists the primitive nondeficient numbers.
%C A337688 The first odd term is 4725.
%H A337688 David A. Corneth, <a href="/A337688/b337688.txt">Table of n, a(n) for n = 1..10000</a>
%H A337688 David A. Corneth, <a href="/A337688/a337688_1.gp.txt">PARI program</a>
%F A337688 Numbers k such that A337690(k) >= 2.
%e A337688 Table of n, a(n) and the relevant divisors starts:
%e A337688    n   a(n)   divisors in A006039
%e A337688    1     60   6, 20;
%e A337688    2     84   6, 28;
%e A337688    3    120   6, 20;
%e A337688    4    140   20, 28, 70;
%e A337688    5    168   6, 28;
%e A337688    6    180   6, 20;
%e A337688    7    210   6, 70;
%e A337688    8    240   6, 20;
%e A337688    9    252   6, 28;
%e A337688   10    264   6, 88;
%e A337688   11    280   20, 28, 70;
%e A337688   12    300   6, 20;
%e A337688   13    312   6, 104;
%e A337688   14    336   6, 28;
%e A337688   15    360   6, 20;
%e A337688   16    420   6, 20, 28, 70;
%o A337688 (PARI) See Corneth link \\ _David A. Corneth_, Oct 07 2020
%Y A337688 A006039 is used to define this sequence.
%Y A337688 Subsequence of: A091192.
%Y A337688 A337689 is a subsequence.
%Y A337688 A337690 is used in a formula defining this sequence.
%K A337688 nonn,easy
%O A337688 1,1
%A A337688 _David A. Corneth_, _Antti Karttunen_ and _Peter Munn_, Sep 20 2020