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A180876
a(n) = sopfr(n) - (floor(sqrt(n))*bigomega(n)).
0
0, 1, 2, 0, 3, 1, 5, 0, 0, 1, 8, -2, 10, 3, 2, -8, 13, -4, 15, -3, 2, 5, 19, -7, 0, 5, -6, -4, 24, -5, 26, -15, 4, 9, 2, -14, 31, 9, 4, -13, 35, -6, 37, -3, -7, 13, 41, -19, 0, -9, 6, -4, 46, -17, 2, -15, 8, 17, 52, -16, 54, 19, -8, -36, 2, -8, 59, -3, 10, -10, 63, -28, 65, 23, -11
OFFSET
1,3
EXAMPLE
Take the number 287. Find the floor of its square root: sqrt(287)=16.941074... it's 16. Now get the factors of 287 = 7*41. Subtract the first prime factor from the floor of the square root: 7-16 = -9. Now subtract the second prime factor from the floor of the square root: 41-16 = 25. Add those values together: -9+25 = 16. It's the same as the floor of the square root. But it doesn't always work out that way.
CROSSREFS
Sequence in context: A346034 A353949 A162517 * A162170 A266770 A282892
KEYWORD
easy,sign
AUTHOR
Jason Earls, Sep 23 2010
STATUS
approved