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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A235591 Numbers which on division by their digital root give quotient which is divisible by its digital root. 0
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 18, 19, 20, 21, 24, 27, 28, 30, 36, 37, 38, 40, 42, 45, 46, 50, 54, 55, 56, 57, 60, 63, 64, 70, 72, 73, 74, 76, 80, 81, 82, 84, 90, 91, 92, 95, 100, 108, 109, 110, 111, 112, 114, 118, 120, 127, 128, 133, 136, 138, 140, 145, 146, 148, 152, 154, 162, 163, 164, 165, 168, 171, 172 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..74.

EXAMPLE

108 is a term as on division by its digital root i.e. 9, gives 12, which is again divisible by its digital root i.e. 3.

MATHEMATICA

dr[n_] := 1 + Mod[n-1, 9]; Select[Range@172, IntegerQ[q = #/dr@#] && Mod[q, dr@q] == 0 &] (* Giovanni Resta, Jan 14 2014 *)

CROSSREFS

Sequence in context: A193456 A143289 A064807 * A007603 A005349 A234474

Adjacent sequences:  A235588 A235589 A235590 * A235592 A235593 A235594

KEYWORD

nonn,base,easy

AUTHOR

Mihir Mathur, Jan 12 2014

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 July 22 10:28 EDT 2018. Contains 312891 sequences. (Running on oeis4.)