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%I #10 Jun 16 2018 19:33:41
%S 20,30,50,70,101,102,104,106,110,111,112,113,114,115,116,117,118,119,
%T 120,121,131,140,141,151,160,161,171,181,191,200,201,203,205,209,210,
%U 211,230,250,290,300,302,304,308,311,320,340,380,401,403,407,409,410
%N Sum of digits of n minus product of digits of n is prime.
%H Harry J. Smith, <a href="/A066027/b066027.txt">Table of n, a(n) for n = 1..1000</a>
%e a(11)=112 because 1 + 1 + 2 = 4, 2*1*1 = 2, and 4 - 2 = 2, which is prime. [corrected by _Harry J. Smith_, Nov 07 2009]
%o (PARI) ProdD(x)= { local(p=1); while (x>9 && p>0, p*=x%10; x\=10); return(p*x) } SumD(x)= { local(s=0); while (x>9, s+=x%10; x\=10); return(s + x) } { n=0; for (m=1, 10^9, if (isprime(SumD(m) - ProdD(m)), write("b066027.txt", n++, " ", m); if (n==1000, return)) ) } \\ _Harry J. Smith_, Nov 07 2009
%Y Cf. A066024, A038369.
%K easy,nonn,base
%O 1,1
%A _Enoch Haga_, Dec 11 2001
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