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A136374
a(n) = (A128677(n) - 1)/(2*A000040(n)).
1
3, 4, 2, 1, 3, 1224, 551, 1, 697, 66, 60, 31, 12, 7, 24641820, 3343240, 122610, 134, 4, 101, 80, 1, 979, 518, 1414
OFFSET
2,1
COMMENTS
All terms are integer since for n > 1, p = A000040(n) divides (A128677(n)-1)/2.
FORMULA
a(n) = (A128677(n) - 1)/(2*A000040(n)).
EXAMPLE
a(2) = (A128677(2) - 1)/(2*A000040(2)) = (19 - 1)/(2*3) = 3.
KEYWORD
nonn,more
AUTHOR
Alexander Adamchuk, Dec 27 2007
EXTENSIONS
a(16)-a(26) from Max Alekseyev, May 14 2010
STATUS
approved