* KKR's stake is enough deterrent for any rival bidder-analyst (Adds analyst comments, share price reaction): SYDNEY (Reuters) - Australian accounting software provider MYOB Group (MYO.AX) said U.S. private equity firm KKR & Co (KKR.N) has launched a conditional A$1.75 billion ($1.24 billion) takeover offer for the company after buying a 19.9 percent stake. KKR, which bought 17 percent of MYOB from its biggest shareholder, made a A$3.70 per share cash offer for the remaining 80.1 percent of the company. The price represents a 24 percent premium to MYOB’s last closing share price and values it at A$2.18 billion.