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!)
A152070 Squares which form nonzero squares when their reversal is subtracted from them. 0

%I

%S 6300100,7502121,16654561,57942544,74753316,696379321,1185424900,

%T 2176315801,16960113361,21735899761,44504965444,52141439025,

%U 95610824100,105593152401,189565322881,213454164121,293481144121,527475375625

%N Squares which form nonzero squares when their reversal is subtracted from them.

%e a(2) = 2739^2 = 7502121 => 7502121 - 1212057 = 6290064 = 2508^2

%t nzsQ[n_]:=Module[{c=Sqrt[n-FromDigits[Reverse[IntegerDigits[n]]]]},c!=0 && IntegerQ[c]]; Select[Range[750000]^2,nzsQ] (* _Harvey P. Dale_, Aug 03 2013 *)

%o (PARI) reverse(expr)=my(v=Vec(Str(expr)),n=length(v));concat(vector(n,i,v[n-i+1])); lista(nn) = {for (n=1, nn, if (issquare(n), rn = eval(reverse(n)); if (n!= rn && issquare(n-rn), print1(n, ", "))););} \\ _Michel Marcus_, Jun 02 2013

%K nonn,base

%O 1,1

%A _Gaurav Kumar_, Jul 24 2009

%E Definition clarified by _Michel Marcus_, Jun 02 2013

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 May 28 21:37 EDT 2020. Contains 334690 sequences. (Running on oeis4.)