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A338249 Nonpositive values in A053985, in order of appearance and negated. 2
0, 2, 1, 8, 7, 10, 9, 4, 3, 6, 5, 32, 31, 34, 33, 28, 27, 30, 29, 40, 39, 42, 41, 36, 35, 38, 37, 16, 15, 18, 17, 12, 11, 14, 13, 24, 23, 26, 25, 20, 19, 22, 21, 128, 127, 130, 129, 124, 123, 126, 125, 136, 135, 138, 137, 132, 131, 134, 133, 112, 111, 114, 113 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

This sequence is a self-inverse permutation of the nonnegative integers (the offset has been set to 0 so as to get a permutation).

There is only one fixed point: a(0) = 0.

LINKS

Rémy Sigrist, Table of n, a(n) for n = 0..10922

Index entries for sequences that are permutations of the natural numbers

FORMULA

a(n) = -A053985(A053754(n+1)) for any n >= 0.

EXAMPLE

A053985 = 0, 1, -2, -1, 4, 5, 2, 3, -8, -7, -10, -9, -4, -3, -6, -5, ...

We keep:  0,     2,  1,              8,  7,  10,  9,  4,  3,  6,  5, ...

PROG

(PARI) A053985(n) = fromdigits(binary(n), -2)

print (-select(v -> v<=0, apply(A053985, [0..147])))

CROSSREFS

Cf. A053754, A053985, A338248.

Sequence in context: A248052 A340629 A105672 * A214271 A262007 A005489

Adjacent sequences:  A338246 A338247 A338248 * A338250 A338251 A338252

KEYWORD

nonn,base

AUTHOR

Rémy Sigrist, Oct 18 2020

STATUS

approved

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Last modified June 15 07:36 EDT 2021. Contains 345043 sequences. (Running on oeis4.)