A357166 If n appears in A357082, then a(n) is the unique k such that A357082(k) = n; otherwise a(n) = -1.

0, 1, 2, 3, 4, 5, 7, 9, 23, 8, 6, 16, 11, 13, 49, 18, 14, 10, 15, 19, 12, 17, 47, 20, 24, 41, 22, 26, 34, 38, 28, 29, 31, 30, 27, 37, 33, 25, 21, 40, 32, 36, 46, 39, 35, 82, 51, 42, 78, 45, 48, 44, 74, 43, 52, 65, 67, 69, 50, 62, 60, 58, 53, 55, 87, 54, 56, 57

Offset: 0

Author

Rémy Sigrist, Sep 16 2022

Keywords

• nonn
• look
• base

Examples

			A357082(42) = 47, hence a(47) = 42.
		

Links

• Rémy Sigrist, Table of n, a(n) for n = 0..10000
• Rémy Sigrist, PARI program
• Rémy Sigrist, Perl program

Crossrefs

Cf. A357082.

Programs

PARI

See Links section.

Perl

See Links section.

Python

from itertools import islice
def agen():
    aset, appearsat, astr, an, mink, nn = {0}, {0: 0}, "0", 0, 1, 0
    for n in count(1):
        k = mink
        while k in aset or bin(an+k)[2:] in astr: k += 1
        while mink in aset: mink += 1
        an = k; aset.add(an); astr += bin(an)[2:]; appearsat[an] = n
        while nn in appearsat: yield appearsat[nn]; nn += 1
print(list(islice(agen(), 68))) # Michael S. Branicky, Sep 16 2022