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Search: id:A083387
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| A083387 |
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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. |
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+0
1
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| 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
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OFFSET
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1,1
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COMMENT
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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 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.
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EXAMPLE
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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.
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CROSSREFS
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Sequence in context: A049603 A035527 A085844 this_sequence A104511 A138876 A060286
Adjacent sequences: A083384 A083385 A083386 this_sequence A083388 A083389 A083390
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KEYWORD
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base,nonn
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AUTHOR
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Jason Earls (jcearls(AT)cableone.net), Jun 11 2003
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