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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A246853 Numbers n such that sigma(n+3) - sigma(n) = n + 3. 4
7, 6285, 4693485, 54028959, 75898473, 724416741, 2359059709, 4901493769, 321212249593, 511578306649, 534245763769, 6158645822473 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Also numbers n such that A001065(n+3) = A000203(n). - Michel Marcus, Sep 06 2014

a(13) > 10^13. - Giovanni Resta, Jul 13 2015

LINKS

Table of n, a(n) for n=1..12.

EXAMPLE

Number 7 is in sequence because sigma(7+3) - sigma(7) = 18 - 8 = 10 = 7 + 3.

PROG

(MAGMA) [n:n in[1..10^7] | SumOfDivisors(n+3)-SumOfDivisors(n) eq n+3]

(PARI)

for(n=1, 10^7, if(sigma(n+3)-sigma(n)==n+3, print1(n, ", "))) \\ Derek Orr, Sep 05 2014

CROSSREFS

Cf. A000203, A067816, A246851, A246852, A246854, A246855.

Sequence in context: A203693 A125036 A098803 * A225067 A281358 A068575

Adjacent sequences:  A246850 A246851 A246852 * A246854 A246855 A246856

KEYWORD

nonn,more

AUTHOR

Jaroslav Krizek, Sep 05 2014

EXTENSIONS

a(4)-a(8) from Hiroaki Yamanouchi, Sep 10 2014

a(9)-a(12) from Giovanni Resta, Jul 13 2015

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
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 15 07:56 EDT 2019. Contains 328026 sequences. (Running on oeis4.)