A076182 a(n) = A006666(n) mod 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
Offset: 1
Keywords
Links
Programs
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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
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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
Formula
a(n) = A006513(n) - 1.
Apparently also the antiparity of A064433. - Ralf Stephan, Nov 16 2004