cp's OEIS Frontend

A277808 a(n) = number of iterations of map k -> A003188(A006068(k)/2) that are required (when starting from k = n) until k is an odious number.

%I A277808 #13 Nov 05 2016 07:25:19
%S A277808 0,0,1,0,1,2,0,0,1,2,0,3,0,0,1,0,1,2,0,3,0,0,1,4,0,0,1,0,1,2,0,0,1,2,
%T A277808 0,3,0,0,1,4,0,0,1,0,1,2,0,5,0,0,1,0,1,2,0,0,1,2,0,3,0,0,1,0,1,2,0,3,
%U A277808 0,0,1,4,0,0,1,0,1,2,0,5,0,0,1,0,1,2,0,0,1,2,0,3,0,0,1,6,0,0,1,0,1,2,0,0,1,2,0,3,0,0,1,0,1,2,0,3,0,0,1,4
%N A277808 a(n) = number of iterations of map k -> A003188(A006068(k)/2) that are required (when starting from k = n) until k is an odious number.
%H A277808 Antti Karttunen, <a href="/A277808/b277808.txt">Table of n, a(n) for n = 1..16384</a>
%H A277808 <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%F A277808 a(n) = A010059(n) * A001511(n).
%F A277808 If A010060(n) = 1 [when n is one of the odious numbers, A000069], then a(n) = 0, otherwise a(n) = 1 + a(A003188(A006068(n)/2)).
%F A277808 Other identities:
%F A277808 For all n >= 0, a(A003945(n)) = n.
%o A277808 (Scheme, with memoization-macro definec)
%o A277808 (definec (A277808 n) (if (= 1 (A010060 n)) 0 (+ 1 (A277808 (A003188 (/ (A006068 n) 2))))))
%o A277808 ;; Other versions:
%o A277808 (define (A277808 n) (if (= 1 (A010060 n)) 0 (A001511 n)))
%o A277808 (define (A277808 n) (* (A010059 n) (A001511 n)))
%Y A277808 One less than A277822.
%Y A277808 A left inverse of A003945.
%Y A277808 Cf. A277812 (gives the odious number where such an iteration is finished at when starting from k=n).
%Y A277808 Cf. A000069, A001969, A001511, A003188, A006068, A010059, A010060, A245710, A268389.
%K A277808 nonn,base
%O A277808 1,6
%A A277808 _Antti Karttunen_, Nov 03 2016