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A283979
a(n) = (n XOR A264977(n))/4, where XOR is bitwise-xor (A003987).
1
0, 0, 0, 0, 0, 1, 0, 0, 0, 3, 2, 3, 0, 3, 0, 0, 0, 7, 6, 5, 4, 4, 6, 7, 0, 5, 6, 5, 0, 7, 0, 0, 0, 15, 14, 9, 12, 10, 10, 9, 8, 10, 8, 8, 12, 10, 14, 15, 0, 9, 10, 15, 12, 14, 10, 9, 0, 9, 14, 9, 0, 15, 0, 0, 0, 31, 30, 17, 28, 22, 18, 21, 24, 20, 20, 18, 20, 16, 18, 17, 16, 22, 20, 22, 16, 21, 16, 16, 24, 16, 20, 18, 28, 22, 30, 31, 0, 17, 18, 27, 20, 28, 30
OFFSET
0,10
FORMULA
a(n) = (n XOR A264977(n))/4, where XOR is bitwise-xor (A003987).
MATHEMATICA
A264977[n_]:= If[n<2, n, If[EvenQ[n], 2 A264977[n/2], BitXor[A264977[(n - 1)/2], A264977[(n + 1)/2]]]]; Table[BitXor[n, A264977[n]]/4, {n, 0, 100}] (* Indranil Ghosh, Mar 28 2017 *)
PROG
(Scheme) (define (A283979 n) (/ (A003987bi n (A264977 n)) 4)) ;; Where A003987bi implements bitwise-xor (A003987).
(PARI) a(n) = if(n<2, n, if(n%2, bitxor(a((n - 1)/2), a((n + 1)/2)), 2*a(n/2)));
for(n=0, 150, print1(bitxor(n, a(n))/4, ", ")) \\ Indranil Ghosh, Mar 28 2017
CROSSREFS
KEYWORD
nonn,base,look
AUTHOR
Antti Karttunen, Mar 25 2017
STATUS
approved