Once upon a time many centuries ago in India, according, a sage gifted a game of war, which he had invented, to a king. This game was Chess .
The king was extremely delighted to receive
this game. He told the sage to ask for any gift he wished. The sage asked the
king to give him as many grains of wheat that would fill the chess board in a
manner that the first square contains one grain, the second 2 grains, the third
4 grains, the fourth 8 grains, and doubling the number of grains in each
successive square till he reached the last square i.e. the sixty-fourth square.
The
king smiled at the sage's request for such a small simple gift, when the sage
could have asked for anything expensive or precious. The king soon realised
that the entire annual grain production wouldn't satisfy the sage's demand.
Actually the wheat demanded is more than the entire world's wheat
production for more than 2000 years. The king was horrified that he wouldn't be
able to honour his word. But the kind sage forgave the king. The king told that he was even more delighted by the
sage's mathematical trick then the game he had gifted him.
How
much do you think is the total number of grains demanded by the sage from the
king?
Here,
the number of grains in each successive squares are doubled. That is, the
common ratio amongst the number of grains in successive squares is 2. Such
sequences of numbers which bear a common ratio amongst successive terms are
called Geometric progression.
2^0 + 2^1 +
2^2 + 2^3 + 2^4 + 2^5 + … + 2^61 + 2^62 + 2^63 = 2^64 – 1
It
is 18446744073709551615.
İst.h/Hatice Uysal Çatmakaş/Salihli Şehit Mustafa Serin AİHL