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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A230355 Nonsquarefree numbers n such that digit sum of n = digit sum of squarefree part of n. 3
12, 24, 60, 100, 120, 132, 150, 156, 200, 204, 228, 240, 264, 276, 300, 320, 348, 372, 420, 500, 516, 552, 600, 624, 636, 660, 700, 708, 732, 744, 780, 912, 1000, 1014, 1050, 1056, 1068, 1092, 1100, 1128, 1164, 1200, 1212, 1216, 1236, 1248, 1272, 1300, 1308, 1320, 1356, 1380, 1392, 1400 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..54.

EXAMPLE

Squarefree part of 624=2^4*3*13 is 39. Digit_sum(624)=12, digit_sum(39)=12

PROG

(PARI)

digsum(n)={local (d, p); d=0; p=n; while(p, d+=p%10; p=floor(p/10)); return(d)}

{for (n=4, 10^3, m=core(n); if(digsum(n)==digsum(m)&&m<>n, print(n))); }

CROSSREFS

Cf. A006753, A230354, A230356, A230357.

Sequence in context: A289132 A098585 A087105 * A063975 A227895 A001335

Adjacent sequences:  A230352 A230353 A230354 * A230356 A230357 A230358

KEYWORD

nonn,base,less

AUTHOR

Antonio Roldán, Oct 16 2013

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 25 04:48 EDT 2017. Contains 289779 sequences.