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Composite numbers n such that the sum of prime factors of n (counted with multiplicity) terminates n as a substring.
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%I #13 Aug 29 2021 11:49:27

%S 4,18,220,230,246,366,444,624,1166,1323,1462,1530,1992,2230,2406,2625,

%T 2730,3024,3125,3182,3286,3484,3606,3760,4220,5733,6372,6435,7592,

%U 8658,8856,9585,9747,10143,10850,11232,11655,13176,13230,13275,13760,14792

%N Composite numbers n such that the sum of prime factors of n (counted with multiplicity) terminates n as a substring.

%C Equals A071173 without its first term. [From _R. J. Mathar_, Sep 13 2008]

%H Harvey P. Dale, <a href="/A143993/b143993.txt">Table of n, a(n) for n = 1..1000</a>

%e a(9)=1166=2*11*53 and 2+11+53=66 and 1166 ends in 66.

%t nssQ[n_]:=Module[{idn=IntegerDigits[n],ss=IntegerDigits[Total[ Flatten[ Table[#[[1]],{#[[2]]}]&/@FactorInteger[n]]]]},Take[idn,-Length[ss]] == ss]; Select[Range[2,15000],!PrimeQ[#]&&nssQ[#]&] (* _Harvey P. Dale_, Sep 03 2012 *)

%K base,nonn

%O 1,1

%A _Gil Broussard_, Sep 07 2008

%E Definition clarified by _N. J. A. Sloane_, Sep 03 2012