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%I #12 Jul 25 2019 12:59:45
%S 4,22,58,85,94,121,166,202,265,274,319,346,355,382,391,454,517,526,
%T 535,562,634,706,778,895,913,922,958,985,1111,1165,1219,1255,1282,
%U 1507,1633,1642,1678,1795,1822,1858,1894,1903,1921,1966,2038,2155,2173,2182,2218
%N Smith semiprimes.
%C Cubefree Smith numbers. This is to cubefree as A202387 is to squarefree. [Jonathan Vos Post, Jan 02 2012]
%H Charles R Greathouse IV, <a href="/A098837/b098837.txt">Table of n, a(n) for n = 1..10000</a>
%F A006753 INTERSECTION A004709.
%e a(3)=58 because 58 is a Smith number as well as a semiprime.
%t sspQ[n_]:=PrimeOmega[n]==2&&Total[Flatten[IntegerDigits/@(Table[#[[1]],#[[2]]]&/@FactorInteger[n])]]==Total[IntegerDigits[n]]; Select[Range[ 2220], sspQ] (* _Harvey P. Dale_, Jul 25 2019 *)
%o (PARI) dsum(n)=my(s);while(n,s+=n%10;n\=10);s
%o list(lim)=my(v=List(),d); forprime(p=2, sqrt(lim), d=dsum(p); forprime(q=p, lim\p, if(d+dsum(q)==dsum(p*q),listput(v, p*q)))); vecsort(Vec(v)) \\ _Charles R Greathouse IV_, Jan 03 2012
%Y Cf. A006753, A004709.
%K base,nonn
%O 1,1
%A _Shyam Sunder Gupta_, Oct 10 2004
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