|
|
A262983
|
|
Terms of A005179 divisible by their indices in order of appearance in A005179.
|
|
4
|
|
|
1, 2, 12, 24, 36, 60, 180, 240, 360, 720, 1260, 1680, 3600, 6720, 5040, 10080, 32400, 15120, 20160, 25200, 60480, 55440, 810000, 100800, 181440, 110880, 226800, 221760, 277200, 907200, 665280, 1587600, 720720, 5670000, 1108800, 3548160, 1995840, 1441440, 2494800, 6350400
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
COMMENTS
|
A005179(n) is in this sequence iff it is divisible by n. Thus this is a subsequence of A005179 indexed by A262981.
It seems that this sequence is a subsequence of A262981.
This sequence is not in ascending order as terms of A005179 divisible by their number of divisors do not occur in ascending order. For terms sorted in ascending order see A110821. - David A. Corneth, Dec 10 2021
|
|
LINKS
|
|
|
FORMULA
|
|
|
EXAMPLE
|
12 is a term since it is the smallest positive integer having exactly 6 divisors and divisible by 6.
|
|
MATHEMATICA
|
Take[#, 33] &@ DeleteCases[#, 0] &@ Function[s, ReplacePart[#, Flatten@ Map[{# -> Function[k, k Boole[Divisible[k, #]]]@ Lookup[s, #]} &, Keys@ s]] &@ ConstantArray[0, Max@ Keys@ s]]@ Map[First, KeySort@ PositionIndex@ Table[DivisorSigma[0, n], {n, 10^7}]] (* Michael De Vlieger, Dec 11 2016, Version 10 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|