With ‘Hindutva’ as the central theme, the Rashtriya Swayamsevak Sangh (RSS) is holding a three-day lecture series from today but the top leaders in the opposition have snubbed the invite. Congress Chief Rahul Gandhi, CPI(M) general secretary Sitaram Yechury and Samajwadi party chief Akhilesh Yadav are not attending the event. The highlight of the event is talks delivered by RSS chief Mohan Bhagwat, presenting the Sangh's view on various contemporary issues. The programme is titled ‘future of Bharat: an RSS perspective.