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A302027
Permutation of nonnegative integers: a(0) = 0; for n >= 1, a(n) = A057889(1+A057889(n-1)), where A057889 is a bijective bit-reverse.
3
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 13, 14, 11, 12, 15, 16, 17, 18, 25, 22, 21, 26, 27, 30, 19, 20, 29, 28, 23, 24, 31, 32, 33, 34, 49, 38, 41, 42, 51, 46, 37, 50, 53, 54, 43, 58, 55, 62, 35, 36, 57, 44, 45, 52, 59, 60, 39, 40, 61, 56, 47, 48, 63, 64, 65, 66, 97, 70, 81, 74, 99, 78, 73, 82, 101, 86, 83, 90, 103, 94, 69, 98, 105, 102, 85
OFFSET
0,3
FORMULA
a(0) = 0; for n >= 1, a(n) = A057889(1+A057889(n-1)).
MATHEMATICA
f[n_] := FromDigits[Reverse[IntegerDigits[n, 2]], 2]*2^IntegerExponent[n, 2]; Fold[Append[#1, f[1 + f[#2 - 1]]] &, {0, 1}, Range[2, 85]] (* Michael De Vlieger, Apr 27 2018, after Ivan Neretin at A057889 *)
PROG
(PARI)
A030101(n) = if(n<1, 0, subst(Polrev(binary(n)), x, 2));
A057889(n) = if(!n, n, A030101(n/(2^valuation(n, 2))) * (2^valuation(n, 2)));
A302027(n) = if(!n, n, A057889(1+A057889(n-1)));
CROSSREFS
Cf. A302028 (inverse).
Cf. A057889.
Cf. also A268717, A302793.
Sequence in context: A337304 A325402 A110029 * A302028 A367600 A023779
KEYWORD
nonn,base,look
AUTHOR
Antti Karttunen, Apr 26 2018
STATUS
approved