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Least composite number with sum of the prime divisors = n, or zero if no such number exists.
1

%I #14 Feb 23 2020 07:09:47

%S 0,4,9,0,6,0,10,15,14,21,121,35,22,33,26,39,210,65,34,51,38,57,273,95,

%T 46,69,285,115,399,161,58,87,62,93,741,155,435,217,74,111,651,185,82,

%U 123,86,129,777,215,94,141,645,235,903,329,106,159,987,265,1645,371,118

%N Least composite number with sum of the prime divisors = n, or zero if no such number exists.

%H Amiram Eldar, <a href="/A093872/b093872.txt">Table of n, a(n) for n = 1..10000</a>

%t sopf[n_] := Plus @@ First @ Transpose @ FactorInteger[n]; m = 100; seq = Table[0, {m}]; c = 0; n = 4; While[c < m - 3, If[CompositeQ[n], s = sopf[n]; If[s <= m && seq[[s]] == 0, c++; seq[[s]] = n]]; n++]; seq (* _Amiram Eldar_, Feb 23 2020 *)

%Y Cf. A008472.

%K nonn

%O 1,2

%A _Amarnath Murthy_, Apr 20 2004

%E Corrected and extended by _Robert Gerbicz_, Aug 21 2006