login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A083389 Numbers n such that the number formed by the digits of 2n sorted in descending order is equal to the sum of the divisors of n after the digits of each divisor have been sorted in descending order (all zeros dropped). 0

%I

%S 37,163,397,4789,16633,19603,19963,31663,48799,49789,166303,169633,

%T 196003,199603,478999,489799,497899,497989,499879,1696033,1966303,

%U 1969633,1999603,3016963,3019663,3169603,3169963,4789999,4798999

%N Numbers n such that the number formed by the digits of 2n sorted in descending order is equal to the sum of the divisors of n after the digits of each divisor have been sorted in descending order (all zeros dropped).

%C Primes with certain digits and various combinations of those digits along with any number of zeros inserted are members. E.g., primes of the form 196(0_z)3, or 3+49*2^(n+2)*5^n for n>1, etc. are in this sequence.

%e a(2)=163 because the digits of 2*163 sorted descending are 632; the divisors of 163 are [1, 163] and 1+631 = 632.

%K base,nonn

%O 1,1

%A _Jason Earls_, Jun 11 2003

%E More terms from _Sean A. Irvine_, May 27 2010

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified February 22 20:26 EST 2019. Contains 320404 sequences. (Running on oeis4.)