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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,12

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..11880

Antti Karttunen, Data supplement: n, a(n) computed for n = 1..100000

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

CROSSREFS

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

Sequence in context: A284445 A288775 A255263 * A173532 A270029 A028598

Adjacent sequences:  A153008 A153009 A153010 * A153012 A153013 A153014

KEYWORD

easy,nonn

AUTHOR

Omar E. Pol, Dec 23 2008

EXTENSIONS

More terms from R. J. Mathar, Feb 19 2009

STATUS

approved

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Last modified November 14 14:43 EST 2019. Contains 329126 sequences. (Running on oeis4.)