King Shehran and Sessa ebn Daher
As the tail says there was a king in India, called Shehran, dominating on everything, but his tedium. He was bored in the morning, noon and at night, all every day, until he fell ill because of it.
Sessa ebn Daher, his court wise man, to heal the king, invented a new game, called it chess. The game was brilliant, the king has recovered from the illnes after the first game.
- What do you want as a reward? - asked Shehran.
- A few grains of wheat only: put one grain on the first square of the chessboard, then double it on the next squares - said Sessa ebn Daher.
- Humble request! - smiled the king, but finally couldn't perform it.
The number of the wheat grains was 18 trillion, 446 billiard, 744 billion, 73 milliard 709 million, 551 thousand 615, which is approximately 700 thousand million tonnes.