A090057 Numbers n divisible by exactly two nontrivial permutations (rearrangements) of the digits of n.

1050, 1080, 3105, 5100, 5400, 7020, 7030, 9207, 9801, 10010, 10050, 10080, 10098, 10200, 10206, 20020, 20160, 20250, 20304, 20400, 20500, 20790, 21000, 21060, 30015, 30030, 30105, 30240, 30420, 30450, 30600, 35100, 40040, 40050

Offset: 1

Author

Chuck Seggelin, Nov 21 2003

Keywords

• nonn
• base

Comments

Trivial permutations are identified as (1) permutation = n, or (2) when n mod 10=0, permutations of n's digits which result in shifting only trailing zeros to the most significant side of n where they drop off, such that permutation = n/10^z, where z <= the number of trailing zeros of n. So if n were 1809000, the following permutations would be excluded as trivial: 1809000, 0180900, 0018090, 0001809.

Examples

			a(3)=3105 because 3105 is divisible by both 135 and 1035, two nontrivial permutations of 3105. a(8)=9207 because 9207 is divisible by both 279 and 297, two nontrivial permutations of 9207.
		

Links

• C. Seggelin, Numbers Divisible by Digit Permutations.

Crossrefs

Cf. A090055, A090058, A090059, A090060, A090061.