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A357166
If n appears in A357082, then a(n) is the unique k such that A357082(k) = n; otherwise a(n) = -1.
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
0,3
LINKS
Rémy Sigrist, PARI program
Rémy Sigrist, Perl program
EXAMPLE
A357082(42) = 47, hence a(47) = 42.
PROG
(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
CROSSREFS
Cf. A357082.
Sequence in context: A293535 A261170 A051453 * A302940 A272072 A118463
KEYWORD
nonn,look,base
AUTHOR
Rémy Sigrist, Sep 16 2022
STATUS
approved