program integralf
      IMPLICIT none
      real*8 t, tmin,dt,intf,tmax
      integer*4 nt,i,n
      write(6,*)' tmin,tmax,nt:'
      read(5,*)tmin,tmax,nt
      dt=(tmax-tmin)/dble(nt-1)
      t=tmin-dt
      n=0
      do 1 i=1,nt
      t=t+dt
1     write(6,600)i,t,intf(t,n),n
600   format(i4,2f12.6,i15)
      end

      function intf(t,n)
      IMPLICIT none
      real*8 t, intf,accu,iold,inew,ymin,ymax,dy,y,u
      integer*4 n,i
c     accuracy in %:
      accu=0.01d0
      iold=0.0d0
      n=2
      ymin=0.0d0
      ymax=1.0d0
100   dy=(ymax-ymin)/dble(n)
      inew=0
      y=ymin-dy/2.0d0
      do 1 i=1,n
      y=y+dy
      u=-log(y)
1     inew=inew+u*sin(u)/(u+t)**6*dy/y
      if(dabs((iold-inew)/inew*100.0d0).gt.accu)then
       n=n+n
       iold=inew
       goto 100
      endif
      intf=inew
      return
      end