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A212739 revision #27

A212739
a(n) = 2^(n^2) - 1.
1
0, 1, 15, 511, 65535, 33554431, 68719476735, 562949953421311, 18446744073709551615, 2417851639229258349412351, 1267650600228229401496703205375, 2658455991569831745807614120560689151, 22300745198530623141535718272648361505980415
OFFSET
0,3
COMMENTS
Number of grains for squared chessboards.
FORMULA
a(n) = 2^(n^2) - 1 = A002416(n) - 1. - Omar E. Pol, Jun 11 2012
EXAMPLE
For usual 8 X 8 chessboard there are 2^64 - 1 = 18446744073709551615 grains.
MAPLE
a:= n-> 2^(n^2)-1:
seq(a(n), n=0..15);
MATHEMATICA
2^Range[0, 12]^2 - 1 (* Paul F. Marrero Romero, Sep 30 2024 *)
CROSSREFS
Sequence in context: A218280 A218632 A218235 * A009068 A268960 A157166
KEYWORD
nonn
AUTHOR
Jani Melik, Jun 06 2012
EXTENSIONS
Better name from Omar E. Pol, Jun 11 2012
STATUS
approved