|
Search: id:A083389
|
|
|
| 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
1
|
|
| 37, 163, 397, 4789, 16633, 19603, 19963, 31663, 48799, 49789, 166303, 169633, 196003, 199603, 478999, 489799, 497899, 497989, 499879
(list; graph; listen)
|
|
|
OFFSET
|
1,1
|
|
|
COMMENT
|
Primes with certain digits and various combinations of those digits along with any amount 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.
|
|
EXAMPLE
|
a(2)=163 because the digits of 2*163 sorted descending are 632; the divisors of 163 are [1, 163] and 1+631 = 632.
|
|
CROSSREFS
|
Sequence in context: A142688 A142197 A140011 this_sequence A142909 A049496 A049497
Adjacent sequences: A083386 A083387 A083388 this_sequence A083390 A083391 A083392
|
|
KEYWORD
|
base,more,nonn
|
|
AUTHOR
|
Jason Earls (zevi_35711(AT)yahoo.com), Jun 11 2003
|
|
|
Search completed in 0.002 seconds
|
