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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A061677 When squared gives number composed just of the digits 1, 2, 3, 4. 1
1, 2, 11, 12, 18, 21, 38, 111, 182, 338, 462, 482, 1111, 1188, 1488, 1521, 2079, 3338, 3368, 3482, 3512, 3639, 4818, 5868, 10688, 11011, 12018, 17639, 17979, 18012, 20521, 20771, 20838, 21079, 33338, 33368, 33632, 34962, 36361, 37739, 37962 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..10001

MAPLE

filter:= t -> convert(convert(t^2, base, 10), set) subset {1, 2, 3, 4}:

select(filter, [seq(seq(x, x=ceil(sqrt((10^i-1)/9)) .. floor(sqrt(4*(10^i-1)/9))), i=1..10)]); # Robert Israel, Mar 01 2016

MATHEMATICA

Do[ If[ Union[ Join[ {1, 2, 3, 4}, IntegerDigits[n^2] ] ] == {1, 2, 3, 4}, Print[n] ], {n, 0, 200000} ]

PROG

(PARI) isok(n) = my(d = digits(n^2)); vecmin(d) && (vecmax(d) <= 4); \\ Michel Marcus, Feb 29 2016

CROSSREFS

Sequence in context: A216213 A160948 A136971 * A110126 A125020 A065020

Adjacent sequences:  A061674 A061675 A061676 * A061678 A061679 A061680

KEYWORD

base,nonn

AUTHOR

Robert G. Wilson v, Jun 23 2001

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 June 25 11:59 EDT 2017. Contains 288710 sequences.