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A081414
Largest prime divisor of prime(2^n+1) - prime(2^n).
0
1, 2, 2, 2, 3, 3, 2, 2, 2, 2, 3, 3, 3, 5, 2, 3, 3, 2, 3, 2, 13, 5, 17, 2, 5, 5, 5, 2, 5, 3, 7, 2, 3, 11, 3, 3, 13, 5, 11, 2, 5, 3, 3, 5, 7, 2, 3, 3, 2, 7, 2, 5, 7, 3, 7, 37, 7, 5, 17, 7, 11, 11, 13, 3, 3, 3, 43, 43, 3, 3, 7, 3, 5, 3, 5, 11, 3, 5, 3
OFFSET
0,2
FORMULA
a(n) = A006530(A001223(A000079(n))) = A081412(2^n) = A006530(A074325(n)).
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Apr 02 2003
EXTENSIONS
Three more terms from Max Alekseyev, May 15 2009
Offset changed to 0, a(0) prepended and more terms added by Amiram Eldar, Jun 04 2024
STATUS
approved