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%I #26 Aug 25 2024 16:38:21
%S 4,22,58,94,166,202,274,346,378,382,438,454,526,562,576,588,634,636,
%T 648,654,666,690,706,728,762,778,852,922,958,1086,1282,1284,1376,1626,
%U 1642,1678,1736,1776,1822,1842,1858,1872,1894,1908,1952,1962,1966,2038
%N Digit sum of composite even number equals digit sum of juxtaposition of its prime factors (counted with multiplicity).
%C Even Smith numbers. - _Robert Israel_, Aug 24 2024
%H Robert Israel, <a href="/A036924/b036924.txt">Table of n, a(n) for n = 1..10000</a>
%p filter:= proc(n) local F;
%p F:= ifactors(n)[2];
%p convert(convert(n,base,10),`+`) = convert(map(t -> t[2]*convert(convert(t[1],base,10),`+`), F),`+`)
%p end proc:
%p select(filter, [seq(i,i=4..10000,2)]); # _Robert Israel_, Aug 24 2024
%t d[n_] := IntegerDigits[n]; co[n_,k_] := Nest[Flatten[d[{#,n}]]&, n, k-1]; t={}; Do[If[!PrimeQ[n] && Total[d[n]] == Total[Flatten[d[co@@@FactorInteger[n]]]], AppendTo[t,n]], {n,4,2040,2}]; t (* _Jayanta Basu_, Jun 04 2013 *)
%Y Cf. A006753, A019506, A036925.
%K nonn,base
%O 1,1
%A _Patrick De Geest_, Jan 04 1999
%E Title made more precise by _Sean A. Irvine_, Nov 30 2020