R n t

R n tR n tR n tR n tR n tR n t
R n tR n tR n tR n tR n tR n t
R n tR n tR n tR n tR n tR n tR n tR n tR n tR n tR n tR n tR n tR n tR n tR n tR n tR n tR n tR n tR n tR n t