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A119562
Let F(n) = 2^(2^n) + 1 = the n-th Fermat number, M(n) = 2^n - 1 = the n-th Mersenne number. Then a(n) = F(n) - M(n) + 1 = 2^(2^n) + 1 - (2^n - 1) + 1 = 2^(2^n) - 2^n + 3.
0
4, 5, 15, 251, 65523, 4294967267, 18446744073709551555, 340282366920938463463374607431768211331, 115792089237316195423570985008687907853269984665640564039457584007913129639683
OFFSET
0,1
FORMULA
a(n) = A001146(n)-A000079(n)+3 = A119564(n)+2. - R. J. Mathar, May 15 2007
EXAMPLE
F(1) = 2^(2^1)+1 = 5
M(1) = 2^1-1 = 1
F(1) - M(2) + 1 = 5
PROG
(PARI) fm2(n) = for(x=0, n, y=2^(2^x)-2^x+3; print1(y", "))
CROSSREFS
Sequence in context: A357927 A051721 A050226 * A289021 A323627 A289742
KEYWORD
nonn
AUTHOR
Cino Hilliard, May 31 2006
EXTENSIONS
Definition corrected by R. J. Mathar, May 15 2007
STATUS
approved