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A139223
M*(M-1), where M is Mersenne prime A000668(n).
5
6, 42, 930, 16002, 67084290, 17179475970, 274876334082, 4611686011984936962, 5316911983139663484697699213480296450, 383123885216472214589586754930667236976614368197214210
OFFSET
1,1
FORMULA
a(n) = A000668(n)*(A000668(n)-1).
KEYWORD
nonn
AUTHOR
Omar E. Pol, May 10 2008
EXTENSIONS
More terms from R. J. Mathar, Jun 24 2009
STATUS
approved