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A071573 a(1) = 1; a(n) = a(n-1)-th nontotient number. 0
1, 14, 114, 594, 2532, 9658, 34066, 113930, 366358, 1141614, 3465398, 10291022, 29988178, 85961454, 242870564, 677436550, 1867877934 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..17.

FORMULA

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

MATHEMATICA

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}]

CROSSREFS

Cf. A005277, A072415.

Sequence in context: A044727 A199251 A199196 * A076429 A027204 A200037

Adjacent sequences:  A071570 A071571 A071572 * A071574 A071575 A071576

KEYWORD

more,nonn

AUTHOR

Robert G. Wilson v, Jun 20 2002

EXTENSIONS

Changed offset to match formula and a(11)-a(17) from Donovan Johnson, Feb 12 2011

STATUS

approved

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Last modified January 20 04:14 EST 2019. Contains 319323 sequences. (Running on oeis4.)