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A071573 a(1) = 1; a(n) = a(n-1)-th nontotient number. 0

%I

%S 1,14,114,594,2532,9658,34066,113930,366358,1141614,3465398,10291022,

%T 29988178,85961454,242870564,677436550,1867877934

%N a(1) = 1; a(n) = a(n-1)-th nontotient number.

%F a(3)=114 is the 14th = a(2)-th term in A005277.

%t a = Table[0, {10^6}]; Do[b = EulerPhi[n]/2; If[b < 10^6 + 1, a[[b]] = 1], {n, 1, 2 10^7}]; b = Select[ Range[10^6], a[[ # ]] == 0 &]; c = 1; Do[ Print[c]; c = 2b[[c]], {n, 0, 7}]

%Y Cf. A005277, A072415.

%K more,nonn

%O 1,2

%A _Robert G. Wilson v_, Jun 20 2002

%E Changed offset to match formula and a(11)-a(17) from _Donovan Johnson_, Feb 12 2011

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Last modified November 30 03:48 EST 2021. Contains 349417 sequences. (Running on oeis4.)