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A083389
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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).
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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; internal format)
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OFFSET
| 1,1
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COMMENTS
| 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.
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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.
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CROSSREFS
| Sequence in context: A178835 A142197 A140011 * A142909 A049496 A049497
Adjacent sequences: A083386 A083387 A083388 * A083390 A083391 A083392
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KEYWORD
| base,nonn
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AUTHOR
| Jason Earls (zevi_35711(AT)yahoo.com), Jun 11 2003
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EXTENSIONS
| More terms from Sean A. Irvine (sairvin(AT)xtra.co.nz), May 27 2010
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