> for all numbers of form n*(n+1)/2+n+2 the answer is 1 and for the
the others is 0

> for all numbers of form n*(n+1)/2+n+2 the answer is 1 and for the
the others is 0

Program Ural1209;
  Const Max=65536;
  Var
    Num:Array[0..Max] Of Longint;
    T:Array[1..Max] Of Byte;
    N,I,K,J,M:Longint;
  Begin
    I:=0;
    K:=0;
    J:=0;
    M:=0;
    FillChar(T,SizeOf(T),0);
    FillChar(Num,SizeOf(Num),0);
    Num[0]:=1;
    For I:=1 To Max Do Num[I]:=Num[I-1]+I;
    Readln(N);
    For I:=1 To N Do
      Begin
        Readln(K);
        If K<1000000000 Then M:=Trunc(Sqrt(K*2))
          Else M:=Trunc(Sqrt(K));
        If K>Num[Max] Then Begin T[I]:=0; Break; End;
        For J:=M-1 To Max-1 Do
          Begin
            If (K>Num[J]) And (K<Num[J+1]) Then Begin T[I]:=0; Break;
End
              Else If (Num[J]=K) Or (Num[J+1]=K) Then Begin T[I]:=1;
Break; End;
          End;
      End;
    For I:=1 To N Do
      If I<>N Then Write(T[I],' ')
      Else Write(T[I]);
  End.

I have no idea the same thing hapens to me too

if sum (sqtr(2*(K-1))) + 1 == K then K==1
else K==0

1250025001

result 1.