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 A083254 a(n) = 2*phi(n) - n. 42
 1, 0, 1, 0, 3, -2, 5, 0, 3, -2, 9, -4, 11, -2, 1, 0, 15, -6, 17, -4, 3, -2, 21, -8, 15, -2, 9, -4, 27, -14, 29, 0, 7, -2, 13, -12, 35, -2, 9, -8, 39, -18, 41, -4, 3, -2, 45, -16, 35, -10, 13, -4, 51, -18, 25, -8, 15, -2, 57, -28, 59, -2, 9, 0, 31, -26, 65, -4, 19, -22, 69, -24, 71, -2, 5, -4, 43, -30, 77, -16, 27, -2, 81, -36, 43, -2, 25 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 COMMENTS Möbius transform of A033879, deficiency of n. - Antti Karttunen, Dec 26 2017 LINKS R. J. Mathar, Table of n, a(n) for n = 1..10000 FORMULA a(n) = totient(n) - cototient(n) = A000010(n) - A051953(n). From Antti Karttunen, Dec 26 2017: (Start) a(n) = A065620(A297153(n)) = A117966(A297154(n)). a(n) = A297114(n) + A297115(n). a(2n) = A297114(2n). For all n >= 1, -a(A000010(n)) = A293516(n). (End) EXAMPLE Case 1# - totient(x)-cototient[x] = 0 if x is a power of 2; Case 2# - totient(x)>cototient[x] gives odd primes and also A067800, (= A014076 except probably A036798); e.g. n = 33: a(33) = 2.20-33 = 7; n = p prime: a(p) = p-2; Case 3# - totient(x)

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Last modified July 29 17:41 EDT 2021. Contains 346346 sequences. (Running on oeis4.)