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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
37, 163, 397, 4789, 16633, 19603, 19963, 31663, 48799, 49789, 166303, 169633, 196003, 199603, 478999, 489799, 497899, 497989, 499879, 1696033, 1966303, 1969633, 1999603, 3016963, 3019663, 3169603, 3169963, 4789999, 4798999 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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.

LINKS

Table of n, a(n) for n=1..29.

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: A140011 A296156 A250842 * A142909 A269259 A269859

Adjacent sequences:  A083386 A083387 A083388 * A083390 A083391 A083392

KEYWORD

base,nonn

AUTHOR

Jason Earls, Jun 11 2003

EXTENSIONS

More terms from Sean A. Irvine, May 27 2010

STATUS

approved

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Last modified October 21 19:08 EDT 2018. Contains 316427 sequences. (Running on oeis4.)