A070843 Largest n-digit number with exactly n distinct prime divisors. There are no further terms.

9, 99, 996, 9996, 99990, 999570, 9999990, 99981420, 999068070, 9592993410

Offset

1,1

Comments

Primes counted without multiplicity. - Harvey P. Dale, Sep 30 2021

Links

Table of n, a(n) for n=1..10.

Example

a(4) = 9996 with the prime divisors 2,3,7 and 17.

Mathematica

Do[k = 10^n - 1; While[Length[FactorInteger[k]] != n, k-- ]; Print[k], {n, 1, 10}] (* Ryan Propper, Nov 05 2005 *)
lnpd[n_]:=Module[{k=10^n-1}, While[PrimeNu[k]!=n, k--]; k]; Array[lnpd, 10] (* Harvey P. Dale, Sep 30 2021 *)

Crossrefs

Cf. A070842.

Sequence in context: A320075 A101564 A242811 * A261512 A242809 A108908

Adjacent sequences: A070840 A070841 A070842 * A070844 A070845 A070846

Keyword

base,nonn,fini,full

Author

Amarnath Murthy, May 12 2002

Extensions

More terms from Rick L. Shepherd, May 14 2002

a(10) from Ryan Propper, Nov 05 2005

Edited by Ray Chandler, Feb 15 2009

Definition clarified by Harvey P. Dale, Sep 30 2021

Status

approved