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!)
A235722 Squares which have one or more occurrences of exactly seven different digits. 3

%I #15 Apr 18 2017 16:18:19

%S 1034289,1046529,1048576,1054729,1056784,1073296,1075369,1085764,

%T 1238769,1247689,1354896,1380625,1382976,1432809,1507984,1605289,

%U 1607824,1630729,1695204,1708249,1750329,1763584,1803649,1827904,1836025,1890625,1946025,1974025

%N Squares which have one or more occurrences of exactly seven different digits.

%C The first term having a repeated digit is 10137856.

%H Colin Barker, <a href="/A235722/b235722.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) = A054035(n)^2.

%e 1247689 is in the sequence because 1247689 = 1117^2 and 1247689 contains exactly seven different digits: 1, 2, 4, 6, 7, 8 and 9.

%t sddQ[n_]:=Count[DigitCount[n],_?(#>0&)]==7; Select[Range[1001,1450]^2, sddQ] (* _Harvey P. Dale_, Mar 12 2015 *)

%o (PARI) s=[]; for(n=1, 10000, if(#vecsort(eval(Vec(Str(n^2))),,8)==7, s=concat(s, n^2))); s

%Y Cf. A235717-A235721, A235723, A235724, A225218.

%K nonn,base

%O 1,1

%A _Colin Barker_, Jan 15 2014

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 March 29 00:26 EDT 2024. Contains 371264 sequences. (Running on oeis4.)