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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A137079 Numbers n such that n and the square of n use only the digits 2, 3, 5 and 6. 1
5, 6, 25, 235, 256, 23566, 2352365325, 23523653335 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Generated with DrScheme

LINKS

Table of n, a(n) for n=1..8.

J. Wellons, Tables of Shared Digits

EXAMPLE

2352365325^2 = 5533622622262355625

MATHEMATICA

fQ[n_] := Block[{d = DigitCount@ n}, Total@ Delete[d, {{2}, {3}, {5}, {6}}] == 0]; Select[Range@ 100000, fQ@ # && fQ[#^2] &] (* Michael De Vlieger, Apr 29 2015 *)

PROG

(Python)

from itertools import product

A137079_list = [int(''.join(a)+b) for l in range(10) for a in product('2356', repeat = l) for b in ('5', '6') if set(str(int(''.join(a)+b)**2)) <= {'2', '3', '5', '6'}]

# Chai Wah Wu, Apr 29 2015

CROSSREFS

Sequence in context: A003226 A088834 A137081 * A163658 A121180 A022165

Adjacent sequences:  A137076 A137077 A137078 * A137080 A137081 A137082

KEYWORD

base,nonn

AUTHOR

Jonathan Wellons (wellons(AT)gmail.com), Jan 22 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 February 23 00:18 EST 2019. Contains 320411 sequences. (Running on oeis4.)