A089256 - OEIS

%I #8 Oct 20 2019 12:47:53

%S 155,274,2191,104579630,142857142,189126664,195488721,241758243,

%T 280035755

%N Numbers n such that decimal expansion of n^2 has the form D 0 (D+1) for some number D.

%C No more terms < sqrt(5)*10^9. - _David Wasserman_, Aug 31 2005

%e 2191^2=4800481 = 480 0 481

%t Select[Table[Sqrt[FromDigits[Join[IntegerDigits[n],{0},IntegerDigits[ n+1]]]],{n,785*10^5}],IntegerQ] (* _Harvey P. Dale_, Oct 20 2019 *)

%K nonn,base

%O 1,1

%A _Yalcin Aktar_, Dec 12 2003

%E More terms from _David Wasserman_, Aug 31 2005