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%I #5 Dec 17 2022 16:43:50
%S 6,6,40,28,473,117,1139,703,3151,5017,496,2701,6683,11051,13207,11183,
%T 20827,10309,26867,20093,18688,12403,27473,91136,18721,101909,63551,
%U 68587,71177,76501,8128,68513,74939,38503,221861,273461,49141,159251
%N Smallest number m such that prime(n) is a factor of both m and sigma(m).
%H Donovan Johnson, <a href="/A156099/b156099.txt">Table of n, a(n) for n=1..5000</a>
%e a(20) = 20093. prime(20) = 71. 20093/71 = 283. sigma(20093)/71 = 288.
%t snm[p_]:=Module[{m=1},While[!Divisible[m,p]||!Divisible[ DivisorSigma[ 1,m],p],m++];m]; snm/@Prime[Range[40]] (* _Harvey P. Dale_, Dec 17 2022 *)
%Y Cf. A000040, A000203.
%K nonn
%O 1,1
%A _Donovan Johnson_, Feb 04 2009
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