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A097521
Difference between F(n) = 2^(2^n)+1 and nextprime(F(n)) where F(n) is the n-th Fermat Number.
1
2, 2, 2, 6, 2, 14, 12, 50, 296, 74, 642, 980, 1760, 896, 2774, 118112, 44060, 5850
OFFSET
0,1
COMMENTS
In the Name, nextprime means A151800, not A007918. - Jeppe Stig Nielsen, Nov 18 2019
a(n) = A129786(n)-1 except in the rare case that F(n) is a prime. - Jeppe Stig Nielsen, Nov 18 2019
FORMULA
a(n) = A013632(A000215(n)). - Michel Marcus, Nov 18 2019
EXAMPLE
F(5) = 4294967297. Nextprime(F(5)) = 4294967311.
4294967311 - 4294967297 = 14 the 6th entry in the table.
PROG
(PARI) for(n=0, +oo, print1(nextprime(2^(2^n)+2)-(2^(2^n)+1), ", ")) \\ Jeppe Stig Nielsen, Nov 18 2019
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Cino Hilliard, Aug 27 2004
EXTENSIONS
More terms with the help of A129786 from Jeppe Stig Nielsen, Nov 18 2019
STATUS
approved