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 A169695 a(n) = 1 if n is a square, otherwise a(n) = 2. 7
 1, 1, 2, 2, 1, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS Also number of central divisors of n, if n >= 1. - Omar E. Pol, Feb 10 2011. Length of n-th row in the array of A207375, if n >= 1. - Omar E. Pol, Feb 27 2012 LINKS Antti Karttunen, Table of n, a(n) for n = 0..65537 FORMULA From Omar E. Pol, Feb 10 2011: (Start) a(n) = 2 - A010052(n). a(n) = 1 + A049240(n), n >=1. a(n) = A000005(n)-A161840(n), n >= 1. (End) MATHEMATICA Array[2 - Boole[IntegerQ@ Sqrt@ #] &, 105, 0] (* Michael De Vlieger, Nov 03 2017 *) CROSSREFS Cf. A010052, A275437. Cf. A000005, A049240, A161840. Sequence in context: A233136 A106054 A275437 * A173642 A234305 A304094 Adjacent sequences:  A169692 A169693 A169694 * A169696 A169697 A169698 KEYWORD nonn,easy AUTHOR N. J. A. Sloane, Apr 15 2010 STATUS approved

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Last modified January 22 15:57 EST 2019. Contains 319364 sequences. (Running on oeis4.)