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A162196
Sum of proper divisors minus the number of proper divisors of nonprime number A018252(n).
2
0, 1, 3, 4, 2, 5, 11, 7, 6, 11, 16, 17, 8, 11, 29, 4, 13, 10, 23, 35, 26, 12, 17, 10, 47, 19, 14, 43, 47, 35, 28, 23, 67, 6, 38, 18, 41, 59, 14, 57, 20, 29, 97, 31, 36, 57, 16, 71, 53, 24, 67, 112, 37, 44, 59, 16, 83, 97, 36, 41, 129, 20, 43, 30
OFFSET
1,3
COMMENTS
Also, zero together with the positive integers of A152770.
Note that the k-th positive integer of this sequence is equal to the sum of proper divisors minus the number of proper divisors of the composite number A002808(k).
FORMULA
a(n) = A152770(A018252(n)).
a(n) = A001065(A018252(n)) - A032741(A018252(n)).
MAPLE
A162196 := proc(n)
end proc: # R. J. Mathar, Sep 28 2011
KEYWORD
easy,nonn
AUTHOR
Omar E. Pol, Jul 04 2009
STATUS
approved