login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A135027 Numbers n such that the sum of the digits of n^2 is 10. n which are multiples of 10 are omitted. 1
8, 19, 35, 46, 55, 71, 145, 152, 179, 251, 332, 361, 449, 451, 548, 649, 4499, 20249, 20251, 24499, 100549, 114499, 316261 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A subsequence of A056020. - R. J. Mathar, Feb 10 2008

No further term between 316261 and 10000000. [From R. J. Mathar, Oct 20 2009]

LINKS

Table of n, a(n) for n=1..23.

EXAMPLE

Corresponding squares are 64, 361, 1225, 2116, 3025, 5041, 21025, 23104, 32041, 63001, 110224, 130321, 201601, 203401, 300304, 421201, 20241001, 410022001, 410103001, 600201001, 10110101401, 13110021001, 100021020121

8^2=64 and 6+4=10. 316261^2=100021020121 and 1+0+0+0+2+1+0+2+0+1+2+1=10. [Zak Seidov, Aug 26 2009]

MATHEMATICA

s={}; Do[If[Mod[n, 10]>0&&10==Total[IntegerDigits[n^2]], AppendTo[s, n]], {n, 10^8}]; s (* Zak Seidov, Aug 26 2009 *)

PROG

Contribution from R. J. Mathar, Oct 20 2009: (Start)

(Python) def A007953(n):

...a=0

...sh=n

...while sh >0:

......a += sh % 10

......sh //= 10

...return a

def isA135027(n):

...if n % 10 == 0:

......return False

...else:

......return A007953(n**2) == 10 ;

for n in range(0, 10000000):

...if isA135027(n):

......print(n)

(End)

CROSSREFS

Sequence in context: A140672 A230098 A262713 * A158916 A045557 A289877

Adjacent sequences:  A135024 A135025 A135026 * A135028 A135029 A135030

KEYWORD

base,more,nonn

AUTHOR

Zak Seidov, Feb 10 2008

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 July 8 01:42 EDT 2020. Contains 335502 sequences. (Running on oeis4.)