A368432 Inverse permutation to A368431.

0, 1, 2, 3, 4, 5, 6, 7, 9, 10, 8, 11, 12, 13, 14, 15, 20, 21, 18, 22, 16, 17, 19, 23, 24, 25, 26, 27, 28, 29, 30, 31, 43, 44, 40, 45, 37, 38, 41, 46, 33, 34, 32, 35, 36, 39, 42, 47, 49, 50, 48, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 90, 91, 86, 92

Offset

0,3

Links

Rémy Sigrist, Table of n, a(n) for n = 0..8191

Rémy Sigrist, PARI program

Index entries for sequences that are permutations of the natural numbers

Example

A368431(42) = 46, so a(46) = 42.

Prog

(PARI) See Links section.
(Python)
from itertools import islice
from functools import reduce
def uniq(r): return reduce(lambda u, e: u if e in u else u+[e], r, [])
def A368431gen():  # generator of A368431
    R, aset = [["0", "1"]], set()
    while R:
        r = R.pop(0)
        for b in r:
            d = int(b, 2)
            if d not in aset: yield d; aset.add(d)
        if len(r) > 1: R.append(uniq([r[k]+"0" for k in range(1, len(r))]))
        R.append(uniq([r[0]+"0", r[0]+"1"] + [r[k]+"1" for k in range(1, len(r))]))
def agen(): # generator of terms
    adict, n = dict(), 0
    for i, k in enumerate(A368431gen()):
        if k not in adict:
            adict[k] = i
        while n in adict: yield adict[n]; n += 1
print(list(islice(agen(), 70))) # Michael S. Branicky, Dec 24 2023

Crossrefs

Cf. A368431.

Sequence in context: A265570 A265554 A082463 * A194962 A072793 A083047

Adjacent sequences: A368429 A368430 A368431 * A368433 A368434 A368435

Keyword

nonn,look,base

Author

Rémy Sigrist, Dec 24 2023

Status

approved