The On-Line Encyclopedia of Integer Sequences (OEIS)

A083387 revision #5

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.

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

1,1

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 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: A085844 A325638 A331752 * A104511 A325021 A325025

Adjacent sequences: A083384 A083385 A083386 * A083388 A083389 A083390

KEYWORD

base,nonn

AUTHOR

Jason Earls (zevi_35711(AT)yahoo.com), Jun 11 2003

STATUS

approved