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A083387 Numbers n such that the number formed by the digits of 2n sorted in ascending order is equal to the sum of the divisors of n after the digits of each divisor have been sorted in ascending order. 0
6, 28, 487, 4204, 17208, 20044, 20404, 25741, 34687, 36847, 41257, 42004, 42571, 48673, 51427, 97398, 125407, 140439, 140527, 200404, 204004, 207541, 250741, 254071, 257401, 304687, 304867, 368047, 402004, 407521, 410257, 425071, 425107 (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 425(0_z)71, or 71+17*2^n*5^(n+2) for n>1 and primes of the form 25(0_z)741 or 741+2^n*5^(n+2) for n>2 etc. are in this sequence.

LINKS

Table of n, a(n) for n=1..33.

EXAMPLE

a(4)=4204 because the digits of 2*4204 sorted ascending are 488; the divisors of 4204 are [1, 2, 4, 1051, 2102, 4204] and 1+2+4+115+122+244 = 488.

CROSSREFS

Sequence in context: A220437 A173360 A085844 * A104511 A138876 A174633

Adjacent sequences:  A083384 A083385 A083386 * A083388 A083389 A083390

KEYWORD

base,nonn

AUTHOR

Jason Earls, Jun 11 2003

STATUS

approved

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Last modified October 23 16:15 EDT 2018. Contains 316529 sequences. (Running on oeis4.)