A125845 n-digit numbers having n divisors each with a different number of digits.

1, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, 121, 169, 289, 361, 529, 841, 961, 1111, 1133, 1177, 1199, 1243, 1313, 1331, 1339, 1391, 1397, 1417, 1441, 1469, 1507, 1529, 1639, 1651, 1661, 1703, 1717, 1727, 1751, 1781

Offset: 1

Author

Joshua Zucker, Dec 11 2006

Keywords

• base
• nonn

Comments

A subsequence of A095862.

Examples

			1 is the only one-digit number with only one factor. Two-digit primes are the only two-digit numbers in the list since they have a one-digit factor (1) and a two-digit factor (themselves). Three-digit squares of two-digit primes are the only three-digit numbers in the list, since only numbers of the form p^2 can have three factors.
		

Links

• Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
• Sam Vandervelde, The Mandelbrot Competition, round 2, 2006-07, asked for the smallest composite number in this list.

Crossrefs

A125315 gives the smallest n-digit number of this form for each n.