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Sum of proper divisors, minus the number of proper divisors, minus cototient of n, plus 1.
2

%I #11 Oct 08 2018 18:10:55

%S 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,

%T 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,

%U 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

%N Sum of proper divisors, minus the number of proper divisors, minus cototient of n, plus 1.

%H Antti Karttunen, <a href="/A153011/b153011.txt">Table of n, a(n) for n = 1..11880</a>

%H Antti Karttunen, <a href="/A153011/a153011.txt">Data supplement: n, a(n) computed for n = 1..100000</a>

%F a(n) = A152770(n) - A051953(n) + 1.

%p 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

%o (PARI) A153011(n) = (2+eulerphi(n)+sigma(n)-numdiv(n)-(2*n)); \\ _Antti Karttunen_, Oct 08 2018

%Y Cf. A000005, A000010, A000203, A001065, A032741, A051953, A152770.

%K easy,nonn

%O 1,12

%A _Omar E. Pol_, Dec 23 2008

%E More terms from _R. J. Mathar_, Feb 19 2009