login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A037043 3-white numbers: partition digits of n^3 into blocks of 3 starting at right; then sum of these 3-digit numbers equals n. 4

%I #13 May 24 2023 18:28:38

%S 0,1,297,1295,1296,1405,1592,1701,1702,1997,1998,1999

%N 3-white numbers: partition digits of n^3 into blocks of 3 starting at right; then sum of these 3-digit numbers equals n.

%C The 1-white numbers are 0 1 2 3 4 5 6 7 8 9; the 2-white numbers are 0 1 45 55 99.

%e 297^3 = 26198073 => 26,198,073 and 26 + 198 + 073 = 297; 1999^3=7988006997 and 7+988+006+997=1999.

%t twnQ[n_]:=Module[{c=IntegerDigits[n^3],a},a=Take[c,Mod[Length[c],3]]; Total[ FromDigits/@ Partition[Drop[c,Length[a]],3]]+FromDigits[a]==n]; Select[ Range[ 0,2000],twnQ] (* _Harvey P. Dale_, Feb 08 2013 *)

%t Select[Range[0, 10^5], # == Plus @@ IntegerDigits[#^3, 10^3] &] (* _Giovanni Resta_, Jul 12 2016 *)

%t Select[Range[0,2000],Total[FromDigits/@(Reverse/@Partition[Reverse[ IntegerDigits[ #^3]],UpTo[3]])] == #&] (* _Harvey P. Dale_, May 24 2023 *)

%Y Cf. A037044, A037045.

%K full,nonn,easy,base,fini,nice

%O 1,3

%A _Erich Friedman_

%E Offset set to 1 by _Paolo P. Lava_, Jul 12 2016

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 24 22:17 EDT 2024. Contains 371964 sequences. (Running on oeis4.)