A positive integer N fulfills the following demands:.
N is a 7 digit number.
N's digits can be arranged as seven distinct members of an arithmetic progression(either ascending or descending) .

N is a multiple of 11.

How many positive integers like N exist?
Evaluate the lowest and the highest N.
BONUS : How about 8 digits? Nine? All ten?
  Rem: It is D4 for fully explained and errorless P&P result,might be significantly lower for software solution.    

3*4*3!*4!=1728

Edited on January 3, 2011, 6:41 pm

Posted by Math Man on 2011-01-03 18:40:37