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%I #98 May 06 2024 11:04:36
%S 4,8,9,16,18,24,25,27,30,32,36,42,49,50,60,64,66,70,72,78,81,84,98,
%T 100,102,105,110,114,120,121,125,126,128,130,132,138,140,144,150,154,
%U 156,160,162,168,169,170,174,180,182,186,190,192,195,196,200,204,216,220,222,228,230,231,234,238,240
%N Composite numbers k that share a factor with sopfr(k), the sum of the primes dividing k, with repetition.
%C All prime powers, see A246547, are terms.
%H Scott R. Shannon, <a href="/A370354/b370354.txt">Table of n, a(n) for n = 1..10000</a>
%e 18 is a term as 18 = 2 * 3 * 3, and soprf(18) = 2 + 3 + 3 = 8, which shares a factor with 18.
%t fn[{a_,b_}]:=a*b;Select[Range[240],CompositeQ[#]&&ContainsAny[First/@FactorInteger[#],First/@FactorInteger[ Total[fn/@FactorInteger[#]]]]&] (* _James C. McMahon_, May 06 2024 *)
%Y Cf. A001414, A002808, A027746, A246547, A046346, A372524.
%K nonn
%O 1,1
%A _Scott R. Shannon_, May 06 2024
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