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A379471
Composition of bijective bit-reverse and Blue code, in this order: a(n) = A193231(A057889(n)).
3
0, 1, 3, 2, 5, 4, 6, 7, 15, 14, 12, 11, 10, 13, 9, 8, 17, 16, 18, 31, 20, 21, 29, 26, 30, 19, 23, 28, 27, 22, 24, 25, 51, 50, 48, 35, 54, 61, 33, 44, 60, 55, 63, 38, 39, 56, 46, 41, 34, 49, 53, 32, 57, 62, 36, 47, 45, 52, 58, 37, 40, 59, 43, 42, 85, 84, 86, 103, 80, 69, 101, 118, 90, 91, 71, 104, 99, 74, 116, 121
OFFSET
0,3
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)));
A193231(n) = { my(x='x); subst(lift(Mod(1, 2)*subst(Pol(binary(n), x), x, 1+x)), x, 2) };
CROSSREFS
Cf. A057889, A193231, A379472 (inverse permutation).
Sequence in context: A340478 A340402 A379472 * A193231 A191672 A273876
KEYWORD
nonn,base,easy
AUTHOR
Antti Karttunen, Dec 25 2024
STATUS
approved