OFFSET
1,2
LINKS
Chai Wah Wu, Table of n, a(n) for n = 1..10000 (n = 1..516 from Harry J. Smith)
EXAMPLE
321 = 3*107, 3 + 2 + 1 = 6 = 3*2*1.
MATHEMATICA
sdpdQ[n_]:=Module[{idn=IntegerDigits[n]}, Total[idn]==Times@@idn]; Module[ {upto=25000, cs}, cs=Complement[Range[upto], Prime[Range[PrimePi[upto]]]]; Select[cs, sdpdQ]] (* Harvey P. Dale, Oct 14 2014 *)
PROG
(PARI) SumD(x)= { local(s=0); while (x>9, s+=x%10; x\=10); return(s + x) } ProdD(x)= { local(p=1); while (x>9 && p>0, p*=x%10; x\=10); return(p*x) } { n=0; for (m=1, 10^9, if (isprime(m), next); if (SumD(m)==ProdD(m), write("b066307.txt", n++, " ", m); if (n==1000, return)) ) } \\ Harry J. Smith, Feb 09 2010
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Labos Elemer, Dec 13 2001
STATUS
approved