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A076182 a(n) = A006666(n) mod 2. 2
0, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10000

Index entries for sequences related to 3x+1 (or Collatz) problem

Index entries for characteristic functions

FORMULA

a(n) = A006513(n) - 1.

Apparently also the antiparity of A064433. - Ralf Stephan, Nov 16 2004

PROG

(PARI) a(n)=if(n<0, 0, s=n; c=0; while(s>1, s=(s%2)*(3*s+1)/2+(1-s%2)*s/2; c++); c)%2

(Scheme)

(define (A076182 n) (modulo (A006666 n) 2))

(definec (A006666 n) (if (= 1 n) 0 (+ 1 (A006666 (A014682 n))))) ;; With memoization-macro definec

(define (A014682 n) (if (even? n) (/ n 2) (/ (+ n n n 1) 2)))

;; Antti Karttunen, Aug 13 2017

CROSSREFS

Cf. A014682, A006513, A006666, A076092.

Sequence in context: A105384 A057212 A023959 * A010058 A140591 A203568

Adjacent sequences:  A076179 A076180 A076181 * A076183 A076184 A076185

KEYWORD

nonn

AUTHOR

Benoit Cloitre, Nov 01 2002

STATUS

approved

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Last modified October 22 06:02 EDT 2018. Contains 316432 sequences. (Running on oeis4.)