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A259366 Numbers for which the differences between consecutive divisors (ordered by size) are not distinct. 3
6, 12, 15, 18, 20, 24, 30, 36, 40, 42, 45, 48, 54, 56, 60, 63, 66, 70, 72, 75, 78, 80, 84, 90, 91, 96, 99, 100, 102, 105, 108, 110, 112, 114, 120, 126, 130, 132, 135, 138, 140, 144, 150, 156, 160, 162, 165, 168, 174, 180, 182, 186, 189, 192, 195, 198, 200 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A060682(a(n)) < A000005(a(n)) - 1.

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

EXAMPLE

.    n |  A193829(n,*)      |  A027750(n,*)         |

.  ----+--------------------+-----------------------+------------

.   10 |  {1,3,5}           |  {1,2,5,10}           |

.   11 |  {10}              |  {1,11}               |

.   12 |  {1,1,1,2,6}       |  {1,2,3,4,6,12}       |  a(2) = 12

.   13 |  {12}              |  {1,13}               |

.   14 |  {1,5,7}           |  {1,2,7,14}           |

.   15 |  {2,2,10}          |  {1,3,5,15}           |  a(3) = 15

.   16 |  {1,2,4,8}         |  {1,2,4,8,16}         |

.   17 |  {16}              |  {1,17}               |

.   18 |  {1,1,3,3,9}       |  {1,2,3,6,9,18}       |  a(4) = 18

.   19 |  {18}              |  {1,19}               |

.   20 |  {1,2,1,5,10}      |  {1,2,4,5,10,20}      |  a(5) = 20

.   21 |  {2,4,14}          |  {1,3,7,21}           |

.   22 |  {1,9,11}          |  {1,2,11,22}          |

.   23 |  {22}              |  {1,23}               |

.   24 |  {1,1,1,2,2,4,12}  |  {1,2,3,4,6,8,12,24}  |  a(6) = 24

.   25 |  {4,20}            |  {1,5,25}             |            .

PROG

(Haskell)

a259366 n = a259366_list !! (n-1)

a259366_list = filter (\x -> a060682 x < a000005' x - 1) [2..]

CROSSREFS

Cf. A193829,  A027750, A060682, A000005, A060683 (complement), subsequence of A129512.

Sequence in context: A239658 A005279 A129512 * A196391 A116359 A141698

Adjacent sequences:  A259363 A259364 A259365 * A259367 A259368 A259369

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jun 25 2015

STATUS

approved

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Last modified May 26 18:08 EDT 2020. Contains 334630 sequences. (Running on oeis4.)