login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A058838 a(n) = 1 + sum of the anti-divisors of n. 6
1, 1, 3, 4, 6, 5, 11, 9, 9, 15, 13, 14, 20, 17, 19, 15, 29, 29, 19, 25, 23, 37, 35, 24, 40, 25, 43, 47, 25, 37, 43, 59, 49, 31, 53, 33, 51, 71, 53, 56, 42, 67, 57, 41, 87, 59, 61, 57, 73, 81, 43, 95, 89, 53, 75, 57, 75, 97, 91, 108, 58, 79, 113, 47, 85 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

See A066272 for definition of anti-divisor.

LINKS

Table of n, a(n) for n=1..65.

Jon Perry, Anti-divisors [Broken link]

Jon Perry, The Anti-divisor [Cached copy]

Jon Perry, The Anti-divisor: Even More Anti-Divisors [Cached copy]

FORMULA

a(n) = A066417(n) + 1.

EXAMPLE

Consider n = 18: 2n-1, 2n, 2n+1 are 35, 36, 37 with odd divisors > 1 {5,7,35}, {3,9}, {37} respectively and quotients {7, 5, 1}, {12, 4}, {1}; so the anti-divisors of 18 are 4, 5, 7, 12. Therefore a(18) = 1 + 28 = 29.

CROSSREFS

Cf. A066417, A066241, A066452.

Sequence in context: A083342 A016655 A057757 * A001177 A053991 A276814

Adjacent sequences:  A058835 A058836 A058837 * A058839 A058840 A058841

KEYWORD

nonn

AUTHOR

Jon Perry, Dec 28 2001

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified February 25 03:06 EST 2018. Contains 299630 sequences. (Running on oeis4.)