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A153011
Sum of proper divisors, minus the number of proper divisors, minus cototient of n, plus 1.
2
1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 4, 0, 0, 0, 4, 0, 5, 0, 6, 0, 0, 0, 14, 0, 0, 2, 8, 0, 14, 0, 11, 0, 0, 0, 24, 0, 0, 0, 20, 0, 18, 0, 12, 8, 0, 0, 36, 0, 9, 0, 14, 0, 24, 0, 26, 0, 0, 0, 54, 0, 0, 10, 26, 0, 26, 0, 18, 0, 22, 0, 65, 0, 0, 10, 20, 0, 30, 0, 50, 10, 0, 0, 70, 0, 0, 0, 38, 0, 68, 0, 24, 0
OFFSET
1,12
FORMULA
a(n) = A152770(n) - A051953(n) + 1.
MAPLE
A000203 := proc(n) numtheory[sigma](n) ; end: A000005 := proc(n) numtheory[tau](n) ; end: A152770 := proc(n) A000203(n)-A000005(n)-n+ 1; end: A051953 := proc(n) n - numtheory[phi](n) ; end: A153011 := proc(n) A152770(n)-A051953(n)+1 ; end: seq(A153011(n), n=1..120) ; # R. J. Mathar, Feb 19 2009
PROG
(PARI) A153011(n) = (2+eulerphi(n)+sigma(n)-numdiv(n)-(2*n)); \\ Antti Karttunen, Oct 08 2018
KEYWORD
easy,nonn
AUTHOR
Omar E. Pol, Dec 23 2008
EXTENSIONS
More terms from R. J. Mathar, Feb 19 2009
STATUS
approved