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A048680
Nonnegative integers A001477 expanded with rewrite 0->0, 01->1, then interpreted as Zeckendorffian expansions (as numbers of Fibonacci number system).
16
0, 1, 2, 4, 3, 6, 7, 12, 5, 9, 10, 17, 11, 19, 20, 33, 8, 14, 15, 25, 16, 27, 28, 46, 18, 30, 31, 51, 32, 53, 54, 88, 13, 22, 23, 38, 24, 40, 41, 67, 26, 43, 44, 72, 45, 74, 75, 122, 29, 48, 49, 80, 50, 82, 83, 135, 52, 85, 86, 140, 87, 142, 143, 232, 21, 35, 36, 59, 37, 61
OFFSET
0,3
COMMENTS
A permutation of the nonnegative integers (A001477). Inverse permutation to A048679, i.e. A048679[ A048680[ n ] ] = n for all n and vice versa.
FORMULA
a(n) = interpret_as_zeckendorf_expansion(rewrite_0to0_1to01(n)) (where rewrite_0to0_1to01(n)=A048678[ n ])
MAPLE
rewrite_0to0_1to01 := proc(n) option remember; if(n < 2) then RETURN(n); else RETURN(((2^(1+(n mod 2))) * rewrite_0to0_1to01(floor(n/2))) + (n mod 2)); fi; end; interpret_as_zeckendorf_expansion := n -> sum('(bit_i(n, i)*fib(i+2))', 'i'=0..floor_log_2(n));
PROG
(PARI) a(n)=my(k=1, s); while(n, if(n%2, s+=fibonacci(k++)); k++; n>>=1); s \\ Charles R Greathouse IV, Nov 17 2013
CROSSREFS
Equals A074049(n+1) - 1.
Sequence in context: A054239 A305424 A371590 * A342793 A178898 A296616
KEYWORD
nonn,easy
AUTHOR
Antti Karttunen, Jul 14 1999
STATUS
approved