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%I #21 Dec 15 2017 17:35:48
%S 1,2,14,22,24,32,42,116,122,126,141,202,211,221,222,260,280,340,402,
%T 411,440,512,620,840,1021,1041,1062,1114,1118,1128,1132,1141,1144,
%U 1201,1202,1206,1218,1222,1242,1250,1314,1332,1340,1380,1401,1411,1602,1611
%N Product of the nonzero digits = number of divisors.
%H Giovanni Resta, <a href="/A066613/b066613.txt">Table of n, a(n) for n = 1..10000</a> (first 1000 terms from Harry J. Smith)
%e 24 is a term as there are 8 divisors of 24 = 2*4.
%t f[n_] := Block[ {a = Sort[ IntegerDigits[n]] }, While[ First[a] == 0, a = Drop[a, 1]]; Return[ Apply[ Times, a]]]; Select[ Range[10^4], f[ # ] == Length[ Divisors[ # ]] & ]
%t pndQ[n_]:=Times@@Select[IntegerDigits[n],#!=0&]==DivisorSigma[0,n]; Select[Range[2000],pndQ] (* _Harvey P. Dale_, Oct 25 2016 *)
%o (PARI) ProdNzD(x)= { local(d, p=1); while (x>9, d=x%10; if (d, p*=d); x\=10); return(p*x) } { n=0; for (m=1, 10^10, if (ProdNzD(m) == numdiv(m), write("b066613.txt", n++, " ", m); if (n==1000, return)) ) } \\ _Harry J. Smith_, Mar 12 2010
%Y Cf. A074312.
%K nonn,base
%O 1,2
%A _Amarnath Murthy_, Dec 24 2001
%E Corrected and extended by _Jason Earls_ and _Robert G. Wilson v_, Dec 26 2001
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